seminar bencana alam - ums...kertas kerja/ editorial: dr. ejria saleh publisiti: cik.farrah anis...
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SEMINAR BENCANA ALAM 2013
1
Perutusan Naib Canselor
Bismillahir Rahmanir Rahim
Assalammualaikum Warahmatullahhi Wabarakatuh dan Salam sejahtera
Syukur ke hadrat Allah S.W.T kerana dengan limpah kurnia-Nya, Seminar Bencana
Alam 2013 dapat dilaksanakan dengan jayanya. Syabas dan tahniah diucapkan di
atas kerjasama antara Unit Kajian Bencana Alam dan Persatuan Geologi Malaysia
serta Jawatankuasa Pelaksana Seminar atas usaha gigih dan dedikasi dalam
memastikan kelancaran seminar ini.
Dengan penganjuran program seumpama ini, pakar-pakar dalam pelbagai
bidang bencana alam dapat menyumbang dan berkongsi hasil penyelidikan,
mewujudkan rangkaian serta mengeratkan hubungan kerjasama di antara satu
sama lain.
Saya berharap agar seminar ini akan mencapai objektif yang disasarkan
bagi menyediakan platform kepada penyelidik untuk membincangkan, berkongsi
serta bertukar idea dan hasil penemuan dalam kajian berkaitan bencana alam.
Adalah menjadi harapan pihak universiti melalui program sebegini, mahasiswa yang
cemerlang dari segi akademik dan sahsiah dapat dilahirkan sejajar dengan Misi
serta Visi Universiti Malaysia Sabah.
Setinggi-tinggi penghargaan dan sekalung budi sekali lagi buat mereka yang
menjayakan seminar ini sama ada secara langsung atau tidak langsung
terutamanya kepada AJK Seminar dan Pusat Pengajian Pascasiswazah atas
kerjasama yang diberikan.
Sekian, terima kasih.
“PENYELIDIKAN DAN INOVASI ASAS KECEMERLANGAN UNIVERSITI”
PROF. DATUK DR. MOHD HARUN BIN ABDULLAH
Naib Canselor
Universiti Malaysia Sabah
SEMINAR BENCANA ALAM 2013
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Kata-Kata Aluan Dekan Sekolah Sains & Teknologi
Bismillahir Rahmanir Rahim
Assalammualaikum Warahmatullahhi Wabarakatuh dan Salam sejahtera
Alhamdulillah, syukur ke hadrat Ilahi, maka dengan izin-Nya, Seminar Pascasiswazah
Sekolah Sains dan Teknologi bejaya dianjurkan pada tahun ini dengan kerjasama
Sekolah Sains dan Teknologi dan Pusat Pengajian Pascasiswazah. Dalam
kesempatan ini saya ingin mengucapakan setinggi-tinggi tahniah dan amat
berbangga dengan komitmen yang diberikan oleh para pensyarah dan para
pelajar pascasiswazah.
Seminar ini diharap dapat menyumbang ilmu dan manfaat kepada semua
pihak terutama para pelajar Pascasiswazah Sekolah Sains dan Teknologi. Selain itu
diharapkan hubungan di antara para pelajar Pascasiswazah dengan para
pensyarah dapat dijalinkan. Secara tidak langsung, seminar ini turut manjadi medan
perkongsian ilmu dalam dalam menghasilkan penyelidikan yang bermutu dan
berkualiti.
Seminar ini juga turut menjadi printis kepada penglibatan mahasiswa dalam
menghasilkan penyelidikan yang dapat diterbitkan ke peringkat yang lebih tinggi.
Akhir kata semoga seminar ini akan tetap diteruskan pada masa akan datang untuk
melahirkan graduan pascasiswazah yang inovatif dan proaktif.
Setinggi-tinggi penghargaan dan sekalung budi sekali lagi kepada AJK pelaksana
dan Pusat Pengajian Pascasiswaza atas sumbangan kewangan yang diberikan.
Tidak lupa juga buat mereka yang menjayakan seminar ini sama ada secara
langsung atau tidak langsung.
“BERTEKAD CEMERLANG”
PROF MADYA DR BABA MUSTA
Dekan Sekolah Sains dan Teknologi
Universiti Malaysia Sabah
SEMINAR BENCANA ALAM 2013
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Kata-Kata Aluan Pengerusi BENCANA 2013
Salam sejahtera
Syukur ke hadrat ilahi, maka dengan izin-Nya, Seminar Pascasiswazah Sekolah Sains
dan Teknologi berjaya dianjurkan pada tahun ini. Seminar Pascasiswazah Sekolah
Sains dan Teknologi merupakan program tahunan yang betujuan untuk
mendedahkan para pelajar Pascasiswazah membentang hasil penyelidikan
mereka . Secara tidak langsung seminar ini diharapkan akan menjadi ruang
kepada para pelajar untuk bertukar-tukar ilmu pengetahuan yang sedia ada.
Pada kesempatan ini setinggi penghargaan dan ribuan terima kasih kami
ucapkan kepada Timbalan Naib Canselor (Akademik & Antarabangsa), Dekan
Pusat Pengajian Pascasiswazah dan Dekan Sekolah Sains dan Teknologi atas
kerjasama dan sokongan untuk kelancaran seminar ini.
Terima kasih juga kepada para pensyarah yang terlibat dalam menjayakan
seminar ini di atas nasihat dan bimbingan yang diberikan. Akhirnya tidak lupa juga
kepada Ahli Jawatankuasa Seminar Pascasiswaza yang merupakan nadi pengerak
seminar atas usaha yang tungkus lumus seminar pada tahun ini. Semoga pada
masa akan datang Seminar pascasiswazah akan lebih giat diadakan untuk
mencapai matlamat, misi dan visi sekolah.
Sekian, Terima Kasih.
“BERTEKAD CEMERLANG”
DR. JUSTIN SENTIAN
Pengerusi
Seminar Bencana Alam 2013
Universiti Malaysia Sabah
SEMINAR BENCANA ALAM 2013
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AHLI JAWATANKUASA SEMINAR BENCANA ALAM 2013
Penaung:
Penasihat:
Prof. Dr. Shahril Yusof
(Timb. Naib Canselor, P&I, UMS)
Prof. Madya Dr. Baba Musta
(Dekan Sek. Sains & Teknologi)
Prof. Dr. Felix Tongkul
(Pengarah, Pusat Penyelidikan &
Inovasi)
Prof. Dr. Sanudin Hj. Tahir
Pengerusi: Dr. Justin Sentian
Timb. Pengerusi: Dr. Ismail Abd. Rahim
(Ketua Unit Kajian Bencana Alam)
Setiausaha:
Bendahari:
Pn. Hazerina Pungut
Pn. Hennie Fitria W. Soehady E.
Seketeriat: En. Mohamed Ali Yusof Bin Mohd Husin
Cik Nabila Mohd. Salleh
Cik Rasyidah Moneey
Cik Hazlinda Ibno
Cik Fatimah Sudirman
Jamuan: Pn. Carolyn Melisa Payus
Pengangkutan/
Kebajikan:
En. Ahmad Norazhar Mohd Yatim
En. Ricardo Nic Jially
Teknikal: En. Junaidi Asis
En. Rezal Rahmat
En. Razuan Matthew
En. Azmie
Kertas Kerja/
Editorial:
Dr. Ejria Saleh
Publisiti: Cik.Farrah Anis Fazliatul Adnan
En. Dazvieo Keniin
Protokol: En. Rodeano Roslee
En. Muzafar Zaki
SEMINAR BENCANA ALAM 2013
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MAJLIS PERASMIAN SEMINAR BENCANA 2013
03 DISEMBER 2013 (SELASA)
AUDITORIUM PERPUSTAKAAN, UNIVERSITI MALAYSIA SABAH.
8.00 pagi Ketibaan dan Pendaftaran peserta
8.30 pagi Ketibaan tetamu kehormat
8.45 pagi Ketibaan YBhg. Prof. Madya Dr. Baba Musta,
Dekan Sekolah Sains dan Teknologi, UMS
9.00 pagi Bacaan Doa
Ucapan Alu-aluan oleh Pengerusi BENCANA 2013
Dr. Justin Sentian
Ucapan Perasmian oleh Dekan SST, UMS
YBhg. Prof. Madya Dr. Baba Musta
9.30 pagi Penyampaian Cenderahati
9.40 pagi Jamuan
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TENTATIF SEMINAR BENCANA ALAM 2013
HARI PERTAMA 3hb DISEMBER 2013 (SELASA)
0830 – 0900 Pendaftaran Peserta (Auditorium Perpustakaan, UMS)
0900 – 0940 Majlis Perasmian (Auditorium Perpustakaan, UMS)
0940 – 1000 JAMUAN
1000 – 1030 Pembentangan Ucaptama:
Prof. Madya Dr. Phua Mui How
PEMBENTANGAN SIDANG A
Pengerusi Sidang :
Dr. Justin Sentian
Sesi Teknikal Penyampai & Tajuk Skop
1030 – 1050 A-01 Prof. Dr. Felix Tongkul
Kajian Bencana Banjir di kawasan
Pekan Tenom.
Banjir
1050 – 1110 A-02 Nauwal Suki & Mohd Hisbany Mohd
Hashim
Preliminary Studies of Construction
Materials Under Tropical Climate
Effects
Perubahan
Iklim
1110 – 1130 A-03 Nurfarhana Diyana Binti Abdul Hadi &
N.H. Abdul Hamid
Lesson Learnt From Past Earthquake
in Malaysia
Gempabumi
1130 – 1150 A-04 Munirah Binti Ariffi & Subramaniam
Moten
The Impact of Tropical Cyclones in
The Western Pacific Ocean and
South China Sea On The Rainfall In
Malaysia
Ribut Tropika
1150 - 1230 SESI PEMBENTANGAN POSTER
1230 – 1400 Makan Tengahari
PEMBENTANGAN SIDANG B
Pengerusi Sidang :
Dr. Ismail Abdul Rahim
Sesi Teknikal Penyampai & Tajuk Skop
1400 – 1420 B-01 Rodeano Roslee, Tajul Anuar
Jamaluddin & Norbert Simon
Urban Geology in Sabah, Malysia
Geologi
Sekitaran
1420 – 1440 B-02 Shamilah Anudai @ Anuar, N.H. Abdul
Hamid & Md. Salleh
Seismic Performance of 3-Storey
Tunnel Form System Building With
Double Units Subjected To Lateral
Cyclic Loading
Gempabumi
1440 – 1500 B-03 Prof. Dr. Wan Mohd. Norsani Wan Nik
Review of Coastline Changes Due To
Erosion at Pantai UMT
Hakisan
Pantai &
Sungai
SEMINAR BENCANA ALAM 2013
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1500 - 1520 B-04 Bala Raju Nikku
1520 – 1540 JAMUAN
1540 – 1600 B-05 Yap Siew Fah
Floods, What Can We Do?
Banjir
1600 – 1620 B-06 Farah Alwani Binti Wan Chik F, T.A.
Majid , S.N.Che Deraman & M.K.A.
Muhammad
An Overview of Windstorm
Phenomenon In Penang State of
Malaysia
Ribut Tropika
1620 – 1640 B-07 Hj Ajak Bin Hj Awang
1640 - 1700 MAJLIS PENUTUPAN
TAMAT HARI PERTAMA
HARI KEDUA 4hb DISEMBER 2013 (RABU)
0900 – 1200 Pameran Poster
SEMINAR TAMAT
SESI POSTER
No. Poster Penyampai & Tajuk Skop
C-01 Norbert Simon, Rodeano Roslee, Nightingle Lian Marto,
Juhari Mat Akhir, Abdul Ghani Rafek & Goh Thian Lai
Lineaments and Their Association with Landslide
Occurrences Along The Ranau – Tambunan Road,
Sabah.
Tanah
Runtuh
C-02 Nurul Adyani Ghazali, Nor Azam Ramli, Ahmad Shukri
Yahaya
Application of Probability Distribution of Predict
Particulate Matter (PM10) Concentration In Malaysia
Perubahan
Iklim
C-03 Mohamed Ali Yusof Bin Mohd Husin & Baba Musta
Effects Of Moisture On The Strength Of Crocker
Formation Soil Along Kota Belud – Ranau Road,
Tamparuli, Sabah.
Tanah
Runtuh
C-04 Dr. Ismail Abd Rahim
The Stability Of Temburung Formation In Beaufort Area,
Sabah
Tanah
Runtuh
C-05
C-06
C-07
C-08
C-09
C-10
SEMINAR BENCANA ALAM 2013
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ABSTRAK
SEMINAR BENCANA ALAM 2013
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A-01
KAJIAN GEOMORFOLOGI BENCANA BANJIR DI DAERAH TENOM, SABAH
Wong Fui Peng & F. Tongkul
Unit Kajian Bencana Alam
Sekolah Sains Dan Teknologi, Universiti Malaysia Sabah
ABSTRAK. Daerah Tenom yang terletak di lembangan Sungai Pegalan dan Sungai
Padas merupakan kawasan yang sering dilanda banjir. Misalnya pada tahun 2009
kejadian banjir yang paling teruk dialami dimana sesetengah kawasan telah
mengalami banjir lebih dari dua meter dan menyebabkan bahaya kepada orang
awam dan kerugian harta benda. Pelbagai usaha telah dilakukan oleh Kerajaan
melalui Jabatan Pengairan dan Saliran untuk mengurangkan masalah ini seperti
penambahbaikan sistem perparitan, pendalaman sungai dan pelurusan sungai,
namun banjir terus berlaku. Untuk mengetahui keseriusan banjir di daerah ini satu
kajian geomorfologi telah dilakukan untuk mengenalpasti taburan kawasan yang
mengalami banjir dan berpotensi untuk banjir, khususnya di sekitar Pekan Tenom.
Untuk kajian ini DTM (IFSAR) oleh Intermap telah digunakan untuk menganalisis
bentuk permukaan bumi. Perisian Global Mapper digunakan untuk mengenalpasti
keluasan kawasan banjir pada ketinggian tertentu dan perisian GIS digunakan
untuk memetakan taburan banjir. Hasil kajian mendapati kawasan yang boleh
dilanda banjir yang berada pada ketinggian dari 174-180 meter mempunyai
keluasan sekitar 3014 hektar. Bahagian barat Sungai Padas yang mempunyai
topografi rendah, adalah yang paling mudah banjir. Walau bagaimanapun
keluasan banjir disini adalah kecil kerana terdapat banyak bukit kecil. Kawasan
yang terletak di bahagian timur Sungai Padas mempunyai keluasan banjir yang
paling besar sebab topografinya agar rata. Kawasan yang berpotensi dilanda
banjir yang berada pada ketinggian 180-181 meter mempunyai keluasan sekitar 364
hektar. Kawasan ini sebahagian besar terletak di utara kawasan kajian, terutama
disebelah timur Sungai Pegalan. Secara umumnya, banjir lebih mudah berlaku di
kawasan sekitar Sungai Padas berbanding dengan Sungai Pegalan kerana ia
mempunyai ketinggian topografi yang lebih rendah.
KATA KUNCI. Sungai Pegalan, Sungai Padas, Topografi, Keluasan banjir, Kawasan
senang banjir.
SEMINAR BENCANA ALAM 2013
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A-02
PRELIMINARY STUDIES OF CONSTRUCTION MATERIALS UNDER TROPICAL CLIMATE
EFFECTS
Nauwal Suki1 & Mohd Hisbany Mohd Hashim2
1,2Faculty of Civil Engineering, Universiti Teknologi MARA,
Shah Alam, Selangor, Malaysia
ABSTRACT. Concrete and steel combination has been used in the construction
industry for years and it is undeniable that it has successfully constructed various
structures. However, tropical climate effects such as the sun rays, chemicals from the
rain or other particles that might be brought by the wind causes corrosion and thus
may affected the structures. This study was done in order to know the extent of
durability of concrete and steel under the harsh tropical climate effects and the
results shall prepare us for the problems that may arise. Through this study, seven
concrete cubes of grade 30 were cast and then cured for different numbers of days.
The cubes are cured for 7, 14 and 28 days. The cubes were then divided and placed
in two different areas; one is an area which has a room temperature surrounding
while the other is exposed to the tropical climate. These cubes were placed there
along with steel for a period of three and six months. Once the exposure time has
lapsed, two tests were done to test the mechanical properties of both construction
materials. Concrete had undergone compression test while steel had undergone
tensile test. After the tests were done, it was shown that the materials which were
placed in room temperature surrounding are more durable and stronger as
compared to its counterpart which were placed in the exposed areas.
KEYWORDS. Preliminary studies, Construction materials, Tropical climate.
SEMINAR BENCANA ALAM 2013
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A-03
LESSON LEARNT FROM PAST EARTHQUAKES IN MALAYSIA
N.D Abdul Hadi1, N.H Abdul Hamid2
1PhD Candidate, 2Assoc. Prof., PhD,
Faculty of Civil Engineering,
Universiti Teknologi MARA,
40450 Shah Alam,
Selangor, Malaysia.
ABSTRACT. This objective of this article is to find the effect of past earthquakes in
Malaysia, and presents a proposed procedure to avoid damages in building caused
by low to moderate earthquake. This research includes findings on potential seismic
sources from Malaysia and neighboring countries and effect of earthquakes to
present structures in Malaysia. A comparative study was done on seismic hazard in
Malaysia from the Sumatran fault. The 2004 Aceh earthquake and 2009 Sumatra
Earthquake are two of the most strong and distant earthquake that has affected
Malaysia. The level of damages on tall buildings in Malaysia following the
earthquakes was found to be predictable at a distance as far as 350km from
potential earthquake sources. Residents in Malaysia, mainly in Selangor and Penang
felt the earthquake and some reported the high intensity of the earthquake caused
cracks on the building. Cracks in structural member indicate a vulnerable structure
especially cracks in column where a diagonal shear crack tends to form. In order to
prevent the formation of cracks, a suitable seismic design code of practice should
be adapted. It is advisable for Malaysia to adapt Eurocode 8 code of practice in
order to avoid further damage of buildings should high intensity earthquake occurs
in Malaysia.
SEMINAR BENCANA ALAM 2013
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A-04
THE IMPACT OF TROPICAL CYCLONES IN THE WESTERN PACIFIC OCEAN AND SOUTH
CHINA SEA ON THE RAINFALL IN MALAYSIA
Munirah Binti Ariffin & Subramaniam Moten
Research Section, Malaysian Meteorological Department,
Jalan Sultan, 46667 Petaling Jaya, Selangor, MALAYSIA.
ABSTRACT. Tropical cyclones (TCs) are intense synoptic systems that significantly
modifies the basic atmospheric state through the entire troposphere. This has a
strong influence on the regional rainfall pattern, even to countries that are not
directly on the path of these cyclones. The Malaysian region is in close proximity to
one of the most active cyclogenesis region in the world, that is the west north
Pacific (WNP) and the South China Sea (SCS) region. This region has the highest
number of TCs globally with an average of 27 cyclones per year, with nearly half of
them reaching typhoon intensity. In this study 57 years of TC data from the Regional
Specialized Meteorological Centre (RSMC) - Tokyo and rainfall data for the same
period from selected principal meteorological stations in Malaysia is used to study
the impact of TCs on the rainfall in three Malaysian regions; Sabah, Sarawak and
northwestern Peninsular Malaysia. The probability of rainfall at different stages of the
cyclone and their location in the WNP and SCS reveals that the rainfall has a higher
probability of occurrence when the cyclone is in the open sea, whereas over
northwest Peninsular Malaysia it is during landfall or close to the Indochina coast the
probability is higher. When the TCs are in the SCS, Sarawak has a higher chance of
getting rain than when the TCs are in WNP. Though the chance of receiving rain
when TCs are located in WNP or SCS is more than 70 percent, but there is less than
40 percent chance of getting heavy rain (>10mm). For Sarawak and northwestern
Peninsular Malaysia when the TCs are located in the SCS, the chance of rain
increases as the TC category increases from depression to typhoon stage. For
Sabah when the TCs are located in WNP, the probability of rain is higher when the
TCs are at the tropical storm stage as compared to other stages.
KEYWORDS. Tropical cyclone, cyclone intensity, rainfall distribution and rainfall
probability.
SEMINAR BENCANA ALAM 2013
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B-01
URBAN GEOLOGY IN SABAH, MALAYSIA
Rodeano Roslee*1, Tajul Anuar Jamaluddin2, S. Abd Kadir S. Omang1 & Norbert
Simon2
1 Program Geologi, Sekolah Sains dan Teknologi, Universiti Malaysia Sabah,
Jalan UMS, 88400 Kota Kinabalu, Sabah
2 Program Geologi, Fakulti Sains dan Teknologi,
Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor
*Email address: [email protected]
ABSTRACT. Urban geology is the study or application of the interaction of human
and natural processes with the geological environment in urbanised areas. Rapid
urbanization in developing countries like Malaysia is directly related to deterioration
of the geo-, eco-systems. It is, therefore, urgent to understand the urban geosystem
and generate the data and awareness amongst planners and/or researchers to
produce long ranging, sustainable and disaster-proof growth. The current status of
work in urban geology area is mainly focused at estimating the levels of pollution,
land use planning, disaster management and other remedial measures apart from
the greater thrust on urban hydrology. In the absence of geological factors, several
studies on urban environments may remain two dimensional, and the urban
development as short sited. Ignorance on sustainable and wise utilization of the
natural resource system made some towns in Sabah, Malaysia quite vulnerable,
affecting physical and mental health of the society. How these factors are
concerned to geology; and the ways the knowledge of geology can help to solve
some of these problems should be of great concern to Urban Geologist. Natural and
human factors have contributed to the occurrence of environmental and
engineering geological problems in Sabah, Malaysia. These include landslides and
slope instability, gullying, building damage, river and coastal erosions, informal
settlements, groundwater quality, industrial pollution, inappropriate solid waste
management, etc (Fig. 1). Besides shaking incident low intensity earthquake results
also provide an opportunity to follow up geological disasters (Fig. 2). The identified
urban geology problems in Sabah, Malaysia require immediate solutions in order to
make the state sustainable. The collection of detailed geological information and
monitoring data, including the engineering geological characteristics of soils,
hydrogeological conditions, slope instability, hydrogeological characteristics,
groundwater quality etc, will serve to increase awareness of the geological impact
on urban development. It is believed that an understanding of these problems will
SEMINAR BENCANA ALAM 2013
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help decision makers or planners devise effective urban policies and land-use
planning strategies. Therefore here is a need to integrate and discuss all these
aspects under single roof of urban geology.
KEYWORDS. Urban Geology, Geo-disaster, Environmental Geology and Sabah.
Figure 1. Some examples of geological disasters ever to occur in Sabah, Malaysia.
Figure 2. Position number epicenter earthquake along the coast of Sabah and the
surrounding which can generate the geological disasters events (Sources from USGS
and JMS (Sabah)).
Kg. Kiau’s landslide (09/05/2012) Land subsidence at Taman Landmark Hagibis Storms (28/11/2007)
Beaufort flood (15/03/2009) Forest burning at Telupid area Kunak earthquake (2008)
SEMINAR BENCANA ALAM 2013
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B-02
SEISMIC PERFORMANCE OF 3-STOREY TUNNEL FORM SYSTEM BUILDING WITH DOUBLE
UNITS SUBJECTED TO LATERAL CYCLIC LOADING
A. A Shamilah, N. H Abdul Hamid & S. M.D Salleh
Faculty of Civil Engineering, Universiti Teknologi MARA, 40450 Shah Alam, Selangor,
Malaysia.
Email : [email protected]
ABSTRACT. A one-third scale of double unit 3-storey reinforced concrete tunnel form
building (TFB) is investigated. A set of 3-storey reinforced building together with
foundation beam are designed, constructed and tested under quasi-static
reversible in-plane lateral cyclic loading. This building is tested from ±0.01% drift until
±1.0% drift with an increment of 0.25% drift. The shear wall of tunnel form system
started to crack at -0.25% (pulling) drift on wall-slab (wall 1) connection of the first
floor. More cracks occurred as the increment of drift on wall surface and the
connection. The diagonal crack found to form at +1.25% drift on the first and second
floor outer wall 3. The diagonal crack also occurred on the second floor of the outer
wall 1. The maximum in-plane lateral loading recorded for this specimen was
71.84KN at +1.0% drift. The ductility of TFB obtained from this experiment result is μ =
4.8 which is still in the range 3 to 6. This showed that TFB performed well under long
distant earthquake for minor to moderate.
KEYWORDS. Tunnel form building system, lateral strength, ductility, stiffness,
equivalent viscous
SEMINAR BENCANA ALAM 2013
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B-03
REVIEW OF COASTLINE CHANGES DUE TO EROSION AT PANTAI UMT
W.B. Wan Nik
Department of Maritime Technology, Faculty of Maritime Studies and Marine
Science, Universiti Malaysia Terengganu, 21030 Kuala Terengganu, Terengganu
ABSTRACT. Marine ecosystem includes the area at the shoreline is the area which
sensitively reacts with any changes occur around it. The changes might affects
either temporarily or permanently. These changes include alteration in morphology,
beach profile and contour. Coastal development creates hazard which affects the
natural environment such as erosion. Reclamation of sand to form a runway for
Sultan Mahmud Airport is an example of coastal erosion due to man-made product.
The aim of this study is to evaluate the changes of the beach near Universiti Malaysia
Terengganu (UMT). This study also provides a few ways to overcome the problem.
The study area was set from Sultan Mahmud Airport to Pantai Mengabang Gelam
which covers the coastline area of 3.4 kilometres. Visual observation was done to the
studied area to see the changes of coastline. It was found that the development of
the runway for Sultan Mahmud Airport has caused severe erosion along this studied
area. There is structural damage along this shoreline and the devastation has
affected socio economy of surrounding resident. This paper reports the erosion
process occurs along the coastline of Tok Jembal and UMT and the method applied
to overcome erosion.
KEYWORDS. erosion, coastal development, rock revetment
SEMINAR BENCANA ALAM 2013
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B-04
SEMINAR BENCANA ALAM 2013
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B-05
FLOODS
WHAT CAN WE DO?
Yap Siew Fah
Department of Irrigation and Drainage Sabah
ABSTRACT: According to the Oxford Dictionary of Current English, flood is the
overflowing or influx of water, especially over land or simple inundation. To the
author, flood is “too much water in the wrong place at the wrong time or that
human are in the wrong place at the wrong time”. As flood can threaten life and/or
property, it is important that these concerns are addressed. This paper highlights the
four basic ways to reduce the threats and their respective merits and constraints.
The four basic ways are the modification of human behavior, modification of the
behavior of flood, modification of properties and living with floods. A few technical
terminologies that are commonly related to flood such as flood frequency,
floodway, flood fringe, flood storage, and flood hazard are included to create a
better understanding of flood and adaptation to flood.
SEMINAR BENCANA ALAM 2013
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B-06
AN OVERVIEW OF WINDSTORM PHENOMENON IN PENANG STATE OF MALAYSIA
F.A. Wan Chik*, T.A. Majid1,2,
S.N.Che Deraman2, M.K.A. Muhammad2
1Disaster Research Nexus, Engineering Campus, Universiti Sains Malaysia 14300
Nibong Tebal, Penang, Malaysia
2School of Civil Engineering, Engineering Campus, Universiti Sains Malaysia, 14300
Nibong Tebal,Penang, Malaysia.
ABSTRACT. During monsoon season, heavy rain and windstorm prone occurred in
micro scale and affected east coast of Peninsular Malaysia and East Malaysia. Aim
of this conducted pilot study is to review on the occurrence of strong wind and
house damaged in five districts in Penang. Data was collected in four years period
from 2010 to 2013 for five respective districts in Penang which acquired from Land
and District Office, thus, all data were analyzed. Meanwhile, the frequencies of
heavy storm occurrence and number of houses damaged have been obtained.
Data comparison between every district in terms of occurrence in month and year
and number of damages were established from the plotted graph. From the graph,
the highest frequency of windstorm occurrence was found at Northern Penang
(SPU), with 538 cases was reported, and followed by Southern Penang (SPS), with 50
cases, Central Penang (SPT), with 29 cases, South West Penang (BD), with 3 cases
and the lowest occurrence at North East Penang (TL), with 2 cases. The highest
number of houses damaged was hampered in year 2012 at Northern Penang (SPU)
with 243 number of houses, while, the least number of houses damaged occurred in
year 2011at North East Penang (TL) by only one house damage. The trend number of
occurrence and damaged also observed step up yearly due to the climate change
and global warming tendency. The important factor that may contribute to climate
change is urbanization. This study shows that windstorm is a phenomenon and must
be considered in Malaysia. It is important to note that a rise in severe windstorm
events, thus, increase the damages and losses and also human life.
KEYWORDS. Wind storm occurrence, frequencies, number of house damaged.
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B-07
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Hj. Ajak Hj Awang
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ABSTRACT.
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C-01
LINEAMENTS AND THEIR ASSOCIATION WITH LANDSLIDE OCCURRENCES ALONG THE
RANAU-TAMBUNAN ROAD, SABAH
Norbert Simon1*, Rodeano Roslee2, Nightingle Lian Marto3, Juhari Mat Akhir1,
Abdul Ghani Rafek1, Goh Thian Lai1.
1School of Environment and Natural Resources Sciences, Faculty of Science and
Technology, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor, Malaysia.
*e-mail: [email protected]
2 School of Science & Technology, Universiti Malaysia Sabah, Jalan UMS, 88400 Kota
Kinabalu, Sabah, Malaysia
3Minerals and Geoscience Department Malaysia (Sabah), Jalan Penampang,
Locked Bag 2042, 88999 Kota Kinabalu,
Sabah, Malaysia.
ABSTRACT. Lineament can be considered as a leading factor in mountainous
regions. These studies associate lineaments with landslide occurrences.. To date, no
guidelines exist and depend on the researcher subjectivity. This study proposes a
simple method to assess the influence of lineaments on landslide occurrences based
on the concept of lineament density. The Ranau-Tambunan districts with a 50 km
road stretch from Ranau to Tambunan, crossing the Crocker and Trusmadi
Formations is selected as the study area. In total, the study area is 87.8 km2. Both
formations have similar area with Crocker (42.6 km2) and Trusmadi (43.8 km2) and
the rest are either igneous and alluvium (1.4 km2). The lineaments were identified
using a 5x5 weighted kernel filter on a RADARSAT-1 standard mode image. The
lineament density was calculated using a 1 km x 1 km grid on the lineament map
and the density for each 1 km2 grid is represented by the total length of lineaments
in a grid. A total of 348 lineaments were identified with the lineament density map
classified into three classes of density, resulting low (<318m), moderate (319-775m),
and high (>775m) using the natural break classification. The presence of lineament is
more pronounced in the Trusmadi compared to the Crocker Formation. The
influence of lineament on landslide occurrences was examined by in tersection of
the lineament density map with 75 landslides observed from fieldwork to determine
the number of landslides in each density class. Out of the 75 landslides, 29 landslides
occurred in the Crocker Formation and the other 46 landslides in the Trusmadi
Formation. From the intersection, a total of 47 landslides were captured into the high
density class. The number of landslides recorded in the high density class in the
Crocker and Trusmadi Formations are 20 and 27 respectively. These results indicate
over half of the landslide occurrences are induced by the presence of lineaments
with with the highest located in the Trusmadi Formation. As a conclusion, this study
demonstrates a simple technique for lineament density determination and its
influence on landslides in an area that consist of two different rock formations.
KEYWORDS. Lineament, lineament density, landslides, filter
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C-02
APPLICATION OF PROBABILITY DISTRIBUTION TO PREDICT PARTICULATE MATTER (PM10)
CONCENTRATION IN MALAYSIA
*Nurul Adyani Ghazali1, Nor Azam Ramli2, Ahmad Shukri Yahaya3
1 Department of Engineering Science, Faculty of Science and Technology, Universiti
Malaysia Terengganu, 21030 Kuala Terengganu, Terangganu, MALAYSIA
2, 3 Clean Air Research Group, School of Civil Engineering, Engineering Campus,
Universiti Sains Malaysia, 14300 Nibong Tebal, Penang, MALAYSIA.
Email: [email protected]
ABSTRACT. Malaysia has experienced several haze events since the 1980s as a
consequence of the transboundary movement of air pollutants emitted from forest
fires and open burning activities. During the haze periods, airborne particulate
matter (PM10) was found as the major pollutant while the other air quality
parameters remained within the permissible healthy standards. The aim of this study
is to determine the best distribution model that will be used to predict the probability
of exceedences and the return periods for PM10. General probability distributions
(i.e., Beta and Inverse Gaussian) were chosen to analyze the PM10 concentrations
data at two different sites in Malaysia represent industrial area namely Johor Bahru
(Johor) and Nilai (Negeri Sembilan). The best models representing the areas were
chosen based on their performance indicator values. The best distributions provided
the probability of exceedances and the return period between the actual and
predicted concentrations based on the threshold limit given by the Malaysian
Ambient Air Quality Guidelines (24-h average of 150 μg/m3) for PM10
concentrations. Results indicated that Beta distribution represents the data better
than Inverse Gaussian distribution model for both sites. The proposed distributions
were successfully used for estimation of exceedences and predicting the return
periods of the sequence year. The best model found in this study was used to
forecast the upcoming haze weather in Malaysia. This information can be used as
basis for issuing advanced warning to the public, such as in cases when prior PM10
could reach its peak concentration at a given day.
KEYWORDS. Beta distribution, Inverse Gaussian distribution, Exceedences, Return
period
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C-03
EFFECTS OF MOISTURE ON THE STRENGTH OF CROCKER FORMATION SOIL ALONG KOTA
BELUD – RANAU ROAD, TAMPARULI, SABAH.
Mohamed Ali Yusof Bin Mohd Husin & Baba Musta
Geology Programme, School of Science and Technology,
Universiti Malaysia Sabah, Jalan UMS, 88400 Kota Kinabalu, Sabah.
Email : [email protected]
ABSTRACT. In Malaysia, landslide are typically associated with heavy rainfall, it is
believe that an increase in the water content of a soil leads to a reduction of the
stability of natural slopes. The research area is located along Kota Belud – Ranau
Road in Tamparuli, it is underlain prominently by Crocker Formation aged from Late
Eocene to Early Miocene. The objective of the study is to determine the effects of
moisture on the strength of various soils from different lithology. Soil of the area is a
weathering product from the exposed sedimentary rock formation known as
Crocker, the alternating different lithology of this formation from one sampling
station to another reflects the diversity in terms of engineering properties. Based from
the Particle Size Distribution Analysis soils from the study area are classified from clay
to sand materials. Moisture data obtained from the Proctor Compaction Test was
applied using the manipulation of Unconfined Compression Test by treating the
samples with 5% of increment and decrement of moisture from the optimum
moisture content. The analysis yielded the strength of soil ranges from 49.5 kPa to
114.5 kPa for optimum moisture, 12.5 kPa to 50 kPa for 5% increment and 77 kPa to
222 kPa for 5% decrement. The term Shear Strength Difference is introduce in this
research, it is define as the percentage of Sample S2 with clayey material scored
75%, the highest percentage of shear strength difference loss when treated with 5%
increase of moisture; it’s a difference from 99 kPa of the shear strength with optimum
moisture to 25 kPa of the shear strength of 5% increase of moisture. Whilst, sample S6
with sandy material scored 145%, the highest percentage of shear strength
difference gain when treated with 5% decrease of moisture; it’s a difference from
90.5 kPa of the shear strength with optimum moisture to 222 kPa of the shear strength
of 5% increase of moisture. It is observed that engineering properties of soil in the
study area provide variety of results and this mainly controlled by the type of soil. This
research shows that effect of moisture to the properties of the sample has a direct
impact on the shear strength of soil.
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C-04
THE STABILITY OF TEMBURUNG FORMATION IN BEAUFORT AREA, SABAH
Ismail Abd Rahim
Natural Disasters Research Unit, School of Sciences & Technology,
Universiti Malaysia Sabah, Jalan UMS
88400 Kota Kinabalu, Sabah, Malaysia
Phone: 088 320000 (5734/5999)
Fax: 088 435324
ABSTRACT. The aim of this paper is to determine the stability and to propose
preliminary rock cut slope protection and stabilization measures for Oligocene to
Late Eocene Temburung Formation in Beaufort, Sabah. Six (6) slopes were selected
for this study. Geological mapping, discontinuity survey, kinematic analysis and
prescriptive measure were used in this study. Results of this study conclude that the
modes of failures are wedge, planar, circular and complex. Gunite, soil nail, weep
hole, slope reprofiling, terrace, drainage and retaining structure are proposed
stabilization and protection measures for the slope in the study area.
KEYWORDS. Temburung formation, Beaufort, mitigation measure, slope stability,
mode of failure
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C-05
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C-06
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C-07
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C-08
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C-09
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C-10
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KERTAS
KERJA
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PRELIMINARY STUDIES OF CONSTRUCTION MATERIALS UNDER TROPICAL CLIMATE EFFECTS
Nauwal Suki1 & Mohd Hisbany Mohd Hashim2
1,2Faculty of Civil Engineering, Universiti Teknologi MARA,
Shah Alam, Selangor, Malaysia
ABSTRACT. Concrete and steel combination has been used in the construction industry for
years and it is undeniable that it has successfully constructed various structures. However,
tropical climate effects such as the sun rays, chemicals from the rain or other particles that
are brought by the wind causes corrosion and thus may affect the structures. This study was
done in order to know the extent of durability of concrete and steel under the harsh tropical
climate effects and the results shall prepare us for the problems that may arise. Through this
study, eight concrete cubes of grade 30 were cast and then cured for 7 and 28 days. The
cubes were then divided and placed in two different areas; one is an area which has a room
temperature surrounding while the other is exposed to the tropical climate. These cubes
were placed there along with steel for a period of three and six months. Once the exposure
time has lapsed, two tests were done to test the mechanical properties of both construction
materials. Concrete had undergone compression test while steel had undergone tensile test.
After the tests were done, it was shown that the materials which were placed in room
temperature surrounding are more durable and stronger as compared to its counterpart
which were placed in the exposed areas.
KEYWORDS. Preliminary studies, Construction materials, Tropical climate.
INTRODUCTION
Concrete and steel are used for construction because these two items need one another.
Concrete has a low tensile strength and needs steel to support it. Steel on the other hand has
a high tensile strength but faces the problem of corrosion if not covered or protected
properly. This is why steel needs concrete to protect it.
We often assume that if a reinforced concrete structure is designed properly, it can stand in
any environment or temperature range without us worrying. We also fail to notice that the
deterioration of concrete may also be caused by other elements, one of which is climate.
Climates are activities that happen within the earth’s atmosphere. The examples are rain,
snow, wind and temperature. Climates depend on the location with different countries
having different climate activities. Based on observations, the deterioration and failure of
buildings occurred due to temperature changes between summer and winter, effects of rain
water and particles carried by wind as well as polluted air (Yaldiz, 2010), heavy loads of snow
on the building and also tougher climate conditions such as hurricane (Kim, 2001) and
chemical reactions that are accelerated by increased temperature and are also influenced
by the humidity (Skalny et al., 2002). Deterioration and failure of structures cost a lot of money
in order to repair the damages and it is a clear reminder on how vulnerable the effects of
climate are. Aware of the signals given by Mother Nature, the climatologists around the
world started finding ways to detect and control changes in extreme weather (Zwiers and
Zhang, 2003). Under tropical climate effects, which is rain and sunny throughout the year, will
cause corrosion to occur. The corrosion, although small in amount, causes small concrete
spillage. Soon, the spillage will grow in size and thus exposing the steel inside the concrete.
SEMINAR BENCANA ALAM 2013
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This situation will then lead to an unexpected modification of the physical properties which
weakens the steel’s tensile strength.
MATERIALS AND METHODS
Concrete cube samples
Eight concrete cubes grade 30 were cast in this study. All concrete cubes with size of 150mm
x 150mm x 150mm were used according to BS8110-4:1997. After the concrete were cast and
left to harden, they were cured in the curing tank for a period of 7 and 28 days. For the
curing process to run smoothly, the curing tank needs to have a temperature between 22oC
to 25oC. (Hamzah et al., 2008). After 28 days, the excess cubes were removed from the
curing tank and placed in two different areas. One area has room temperature settings
while the other is exposed to the tropical climate for the periods of 3 and 6 months. All these
cubes were then tested using a 3000kN compression machine as shown in Figure 1.
Steel samples
The standard codes for reinforcement which were used in this study are BS4449:1998 and
BS4482:1985. Nine steel rods were used in this study. The steel rods were divided into three
different functions. Three rods were used as control samples, another three rods were
exposed for a period of 3 months while the last three rods were exposed for a period of 6
months. All the steel rods have a diameter of 12mm with a tensile strength of 460N/mm2.
These steel rods were cut 750mm in length. They were then tested using the universal Testing
Macine (UTM) which has the capacity of 1000kN as shown in Figure 2. Using the UTM, steel is
gripped on both sides; lower part and upper part. The lower part of the grip is a fixed grip
while the upper part is a moving grip. The Extensometer is attached to the steel to measure
the elongation.
Figure 1. Compression Test Figure 2. Tensile Test
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RESULTS AND DISCUSSIONS
Compression Test
Concrete is a material which has high compression strength. Concrete strength can be
determined through compression test. Compression test is able to give us a view of the
quality of concrete in its hardened state. Compression test is done to determine the
maximum compressive strength and the maximum load that a concrete could bear. Table 1
shows the tabulated data for compression test for the periods of 7 and 28 days. Based on the
data, the concrete is seen to have properly developed in proportion to the period of days it
takes to cure.
Table 1. Compression Test Results for 7 and 28 Days.
Cube
ID
Weight
(g)
7 Days 28 Days
Compressive
Strength
(N/mm2)
Maximum
Load
(kN)
Compressive
Strength
(N/mm2)
Maximum
Load
(kN)
Cube 1 7923.6 24.48 550.8 - -
Cube 2 8012.2 22.41 504.2 - -
Cube 3 7954.4 - - 31.50 708.8
Cube 4 7796.7 - - 29.18 656.4
After 28 days, the excess cubes were removed from the curing tank and placed in two
different areas. One area has room temperature settings while the other is exposed to the
tropical climate for the periods of 3 and 6 months. Upon reaching the exposed periods,
compression test was done unto the concrete cubes and the data was tabulated and can
be seen in Table 2. The curve for compression test data was plotted in Figure 3. It was found
that the compression strength of the cubes that were exposed did not reduce or deteriorate
from the original grade (grade 30). That being said, the compressive strength did reduce and
the maximum load that they could bear was less when compared to the cubes placed in
room temperature settings.
Table 2. Compression Test Results for 3 and 6 Months
Cube
ID
Condition
Weight
(g)
3 Months 6 Months
Compressive
Strength
(N/mm2)
Maximum
Load
(kN)
Compressive
Strength
(N/mm2)
Maximum
Load
(kN)
Cube 5 Room Temperature 7680 36.79 827.7 - -
Cube 6 Tropical Climate 7760 33.97 764.3 - -
Cube 7 Room Temperature 7640 - - 36.82 828.4
Cube 8 Tropical Climate 7800 - - 35.54 799.7
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Figure 3. Compressive Strength versus Number of Days Curves
From the physical side of the observation, the tropical climate effects did not provide
extreme effects to the concrete. The concrete cubes which were exposed for 3 months has
the same physical attributes when compared to the cubes placed in room temperature
settings; in short, there were no physical changes. This can be seen in Figure 4(a). Figure 4(b)
shows the concrete cubes that were exposed to tropical climate for 6 months. There were
slight colour changes in certain areas and small stone spillage at the edges of the cubes.
(a) 3 Months Exposed (b) 6 Months Exposed
Figure 4. Concrete Cubes Exposed to Tropical Climate
Tensile Test
Tensile test is done to determine the tensile strength. Tensile strength is the most important
property for steel. Tensile test can also provide the data for elongation at fracture. Table 3
tabulates the average data for maximum load; tensile strength and deformation while Figure
5 shows the tensile strength data versus deformation which has been plotted. It was found
that after being exposed, the load that can be bore was reduced. The tensile strength was
also reduced. Moreover, the elongation of steel at rupture was seen to be longer.
Table 3. Tensile Test Results for Control and Exposed Steel Samples.
Condition Load
(kN)
Tensile Strength
(N/mm2)
Deformation
(mm)
Control 86.23 762.45 25.38
3 Months Exposed 85.60 756.89 25.82
6 Months Exposed 83.72 740.29 29.51
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Figure 5. Tensile Strength versus Deformation Curves
Figure 6 shows steel failure at rupture. All steel rods faced ductile failure. Figure 6(a) is the
control steel sample, Figure 6(b) is the steel exposed for 3 months and Figure 6(c) is the steel
exposed for 6 months. As time goes by, it was seen that the oxidization process became bad
to worse. It is seen that the steel exposed for 3 months was partially oxidized while the steel
exposed for 6 months was almost completely oxidized.
(a) Control (b) 3 Months Exposed (c) 6 Months Exposed
Figure 6. Steel for Control, 3 and 6 Months Exposed Samples
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CONCLUSION
Steel is used in construction to support concrete to withstand under tensile and thus avoid
cracking. To ensure that steel remains strong and concrete does not crack, both need to
always be strong and support each other. Due to tropical climate effects, the strength of
steel was reduced. To avoid the unwanted condition to happen, the concrete needs to be
ensured that it can properly protect the steel. Maintenance need also be done often to
ensure concrete spillage due to tropical climate effects does not increase and the concrete
will properly protect the steel within its expected lifetime. We have to take the climate
impact into the design and construction process. Further research needs to be carried out for
different regions so that strategies can be identified and can cope with expected climate
risks. If designed properly; with consideration of climate effects, the combination of these two
materials can produce a structure that can withstand various conditions. However, the results
of current research about the durability of these two materials under tropical climate effects
are scattered in journals and are only mentioned a little in different journals or in text books or
revision books. It is hoped that more insight and information will be found which in the end
reduce the gap of study regarding tropical climate effects to construction materials.
REFERENCES
British Standard Institution, (1997), BS8110-1 Structural Use of Concrete: Code of Practice for
Design and Construction, Milton Keynes:British Standard Institution
British Standard Institution, (1988), BS4449 Specification for Carbon Steel Bars for the
Reinforcement of Concrete, Milton Keynes, British Standard Institution
British Standard Institution, (1985), BS4482 Specification for Cold Reduced Steel Wire for the
Reinforcement of Concrete, Milton Keynes, British Standard Institution
Jan Skalny, Jacques Marchand and Ivan Odler, (2002), Sulfate Attack on Concrete, SPON
Press
Kim, R. L., (2001), Effects of Climate Change on Built Environment, Norwegian Building
Research Institute (NBI).
Siti Hawa Hamzah, Nor Hayati Abdul Hamid and Mat Som Marwi, (2008), Understanding
Reinforced Concrete Through Experiment (2nd Edition), University Publication Centre (UPENA)
Yaldiz, E., (2010), Climate Effects on Monumental Buildings, 4th International Scientific
Conference on Water Observation and Information System for Decision Support,
BALWOIS2010, Ohrid, Republic of Macedonia, 25-29 May 2010.
Zwiers, F. W., and Zhang, X., (2003), Towards Regional Scale Climate Change Detection,
Journal of Climate, Vol. 16, Page 793-797.
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LESSON LEARNT FROM PAST EARTHQUAKES IN MALAYSIA
N.D Abdul Hadi1, N.H Abdul Hamid2 1PhD Candidate, 2Assoc. Prof., PhD,
Faculty of Civil Engineering,
Universiti Teknologi MARA,
40450 Shah Alam,
Selangor, Malaysia.
ABSTRACT. The purpose of this paper is to find the effect of past earthquakes in Malaysia and
to discuss the lesson learnt from past earthquake either in Malaysia or around Malaysia. .This
includes the damages of structure and infrastructure following the earthquake at
neighboring countries such as Sumatera, Philippines and others. The 2004 Aceh earthquake
and 2009 Sumatra Earthquake are two of the most strong and distant earthquake which has
significant effects to Malaysia. The level of damages on tall buildings in Malaysia following
the earthquakes was found to be slightly damage with minor cracks on the walls and beam
even though at a distance as far as 350km from epicenter. The residents of high rise building
in Selangor and Penang felt tremors after earthquake and it is reported that the high intensity
of the earthquake caused some cracks on the multi-storey building. Cracks in structural
members indicate that this structure which designed according to BS8110 (without seismic
loading) is vulnerable to moderate and severe earthquake. In order to prevent the
formation of cracks, a suitable seismic design code of practice should be adapted. It is
advisable for Malaysia to adapt Eurocode 8 (EC8) in order to avoid further damage of
buildings under high intensity of earthquake in Malaysia.
KEYWORDS. Moderate Earthquakes, Seismic Hazard
INTRODUCTION
Seismicity of an area refers to the frequency, type and size of earthquakes experienced over
a period of time. Malaysia is located on a relatively stable Sundaland block which forms the
southern edge of the Eurasian plate (Azhari, 2012) and it is known to have low seismicity
region. Two main sources have been identified as the contributors to earthquake hazard in
Peninsular Malaysia, namely the Sumatra strike-slip fault and Sumatra subduction zone. It is a
fact that the nearest earthquake fault line in Malaysia which is located in Sumatra comprises
of Sumatra subduction zone and Sumatra fault line with more than 350 km away from Klang
Valley. However, every year, the tectonic plates are moving closer to Malaysia at a rate of
70mm/year. Therefore, precaution steps should be made to prepare the Malaysian from
devastating event and to learn from other earthquakes occurs around the world. The
objective of this paper is to highlight the lessons learnt from previous earthquake in Malaysia
as well as the possible effect that may occur at structures and to provide a viable solution in
preparing for future earthquakes either in or around Malaysia. Figure 1 shows the Sumatran
fault line and subduction of the Indian-Australian Plate and Eurasian Plate. Malaysia has not
experienced high intensity earthquake except for the ones from the neighboring countries.
Up to date, only the 2004 Banda Aceh earthquake had caused the most casualties in
Malaysia due to the tsunami effect especially at northern part of Peninsular Malaysia.
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Figure 1: Sumatran fault and subduction of the Indian-Australian Plate and Eurasian Plate
(Balendra et al. 2001).
EARTHQUAKES IN MALAYSIA
Most of the earthquakes that occurred in Malaysia in the past 10 years are mainly in Sabah
with its epicenters in Lahad Datu, Kudat and Ranau with a range of 4.5 to 5 magnitudes.
These earthquakes are caused by the fault lines in Sabah such as Mendasan fault line and
Lobou-Lobou fault line. However, there were some phenomena recorded in Peninsular
Malaysia such as sink hole in Ipoh and Batu Gajah, tremors in Bukit Tinggi area in 2008 and
tremor at Jerantut in 2009 (Omar, 2009). In a more recent event, the Malaysia Meteorological
Department(MMD) reported that a mild earthquake of magnitude 3.8 Richter scale struck
Kupang with its epicenter located at 11km south of Baling. The phenomena might triggered
by the large earthquake events in neighboring countries. The local earthquakes in Peninsular
Malaysia are the results from the few inactive fault lines namely, Bukit Tinggi Fault, Kuala
Lumpur Fault, Lebir Fault, Baubak Fault and Mersing fault which is situated across the states as
published by the DMGM in 2008 as shown in Figure 2.
Figure 2: Location of major and minor fault lines in Peninsular Malaysia (DMGM, 2008)
SEMINAR BENCANA ALAM 2013
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However, the tremors that were felt in Peninsular Malaysia usually come from the long distant
earthquake with its epicenter in the neighboring country, namely, Sumatera. The 2002
Northern Sumatra earthquake which causes tremors in west Peninsular Malaysia occurred as
a result of thrust faulting on the boundary between the subducting Australian plate and the
overriding Sunda block of the Eurasian plate (Azlan et al., 2002). Malaysia is also one of the
countries that were affected by tsunami from Banda Acheh, Sumatra. Tremors were felt in
several cities in states of Peninsular Malaysia such as Penang and Selangor. High magnitude
earthquake can cause a great impact to the surrounding location and also to those located
far from its epicenter. The high frequency earthquake waves damped out rapidly in the
propagation while the low frequency or long period waves are more robust to energy
dissipation and as a result they travel long distances (Balendra and Li, 2008). Therefore, large
earthquake magnitude from Indonesia will always cause tremors to Malaysia.
SUMATRAN SUBDUCTION ZONE
The Sumatran subduction zone is formed by subduction of the India-Australian plate beneath
the Eurasian plate at a rate of about 70mm per year (Hamilton, 1979). The nearest location of
this Sumatran fault line is about 350km to Peninsular Malaysia (Adnan and Irsyam, 2002)
which relatively far from the seismic source zone. However tremors due to the Sumatra
earthquakes had been reported several times in local newspaper. In the last few years,
tremors were felt several times in tall buildings which located in Singapore and Kuala Lumpur,
due to the high magnitude earthquake in Sumatra, Indonesia. Based on past earthquake
events such as the 2004 and 2013 Aceh Earthquake and the 2009 and 2011 Northern
Sumatra Earthquake, the range of earthquake magnitude in Indonesia that caused tremors
in Malaysia is within the range of 6.1 to 9.3 scale magnitude. Figure 3 shows the location of
epicenters of the earthquake which located along the Sumatran fault. Even though Malaysia
is situated at more than 300km away from the epicenters, the earthquake can be threat to
the residents who live in high rise buildings in Malaysia especially in West Peninsular.
Figure 3. Location of epicenters of earthquake in Sumatran fault (USGS, 2002)
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According to the historical records in the last 300 years, four great earthquakes have
occurred in Sumatera sismic zone (Balendra and Li, 2008). Major tectonic feature of Sumatra
seismic area is the Sunda Arc which extends between the Andaman Island in the northwest
and the Banda Arc in the east which results in the subduction of the Indo Australian plate
beneath the Sunda Shelf to a stable southern prolongation of the Eurasian plate. The
frequency and magnitude of this subduction zone seismicity is influenced by the age,
composition, and rate of convergence of the subducted plate. The largest thrust-fault
earthquakes in the Sumatra subduction zone in the last two centuries were that of 1833,
which had a magnitude of 8.8 to 9.2, and that of 1861, which had a magnitude of 8.3 to 8.5
(Adnan and Irsyam 2002). The Sumatran Subduction Zone is also influenced by strike-slip
faulting as a result of the component of plate-motion that is parallel to the trend of the plate
boundary in the interior of the island of Sumatra. Figure 4 shows the Sumatran subduction
zone and Sumatran fault line which located at the offshore and inland, respectively.
Figure 4: The Sumatran Subduction Zone (Adnan and Irsyam, 2002)
SEISMIC HAZARDS IN MALAYSIA
The study of the expected earthquake ground motions at the surface of the earth, and its
likely effects on existing natural conditions and man-made structures is important in
preparation of future earthquake in Malaysia. The most common parameters that are
considered in seismic hazard assessment are recurrence rate and maximum magnitude of
earthquake from future source. Delfebriyadi (2011) studied the seismic hazard analysis to
predist the peak ground acceleration (PGA) at bedrock of Kuala Lumpur. It was found that
at a return period of 475 years, the PGA is 0.08g while Sooria et al (2012) proposed that a
maximum earthquake magnitude in Peninsular Malaysia is 6.5 and the allowable
displacement due to ground motion is 150mm. This falls under moderate earthquake,
therefore, structures in Malaysia should have seismic provisions in order to resist earthquake
excitation in the future.
It is well recognized that ground motions due to earthquakes are affected by the
earthquake source condition, the source-to-site transmission path, and site conditions
(Huang, 2013). Balendra and Li (2008) conducted a research on seismic hazard in Malaysia
through attenuation model. It was found that the major reason that resulted in an obvious
ground motion at a great distance is due to the types of soil. The bedrock motions can be
significantly amplified when the natural period of the soft soil is close to the predominant
natural period of the bedrock motions, and can be further enlarged if the building possesses
SEMINAR BENCANA ALAM 2013
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a natural period which is close to the natural period of the site. Putrajaya and Klang are
sitting on soil that is most susceptible to tremors. Therefore, it explains the shaking felt by the
residents of high rise building. Although Malaysia is situated at low seismic region, it is very
important to not neglect the possible earthquake effects. Figure 5 shows the seismic hazard
map for Indonesia and Malaysia which can be used as the basis of seismic design of building
and infrastructures for the closer location and place.
Figure 5: Seismic Hazard Map in Indonesia and Malaysia (USGS, 2008)
LESSONS LEARNT FROM PAST EARTHQUAKES
Damages, Retrofitting and Code of Practice
Earthquake can cause buildings to collapse, loss of lives and also affect downturn economy
for particular countries. Most of reinforced concrete structures in Malaysia are not able to
resist moderate or major earthquake since they are designed according to BS8110 which has
no seismic provisions at all. Some of the common deficiency includes poor reinforcing
detailing, low concrete strength and inadequate construction quality of members causing
strong beam weak columns phenomena. Therefore, it is of great concern that the strength,
ductility, and energy dissipation capacity of these frame structures may not be adequate to
sustain earthquake-induced loads due to the lack of reinforcement details in this type of
structures (Li and Pan, 2004). One of the most common damage found on reinforced
concrete column subjected to earthquake loading is shear failure. It usually occur as a result
of inadequate transverse reinforcement in the joint and weak-column/strong-beam design
(Ghobarah and Said, 2002). For non-ductile design structures, joint shear failure is very
common when subjected to earthquake excitation. Under seismic loading, it is important for
an RC building to have resistance against brittle failure as it does not have high ductility.
Since demolishing and reconstructing buildings are not a great option due to economic
reasons, retrofitting them at a small fraction of total cost of a new building may offer a
workable solution for ensuring the safety of the people.
Although Peninsular Malaysia has experienced shaking due to mild earthquake, no
significant damage has ever occurred in any multi storey reinforced concrete buildings.
However, in East Malaysia, past earthquakes and ground deformation have resulted in
extensive damage to infrastructures in the area, specifically to schools and teacher’s
quarters (Mohamed, 2012). Buildings of operational damage can be retrofitted suit to
SEMINAR BENCANA ALAM 2013
44
damage conditions. Other precaution in preparing Malaysia towards earthquake is
developing an appropriate seismic code of practice such as Eurocode 8 to replace BS8110
in designing multi storey reinforced concrete buildings. Therefore, Malaysia should adapt the
seismic design code of practice in reinforced concrete and steel building, especially for high
rise buildings to avoid experiencing major structural damages during an earthquake.
CONCLUSION
A detail review on seismic hazard study of the regions near Peninsular Malaysia and Sabah
and Sarawak has shown that it is not impossible for large magnitude earthquake will occur in
Malaysia. The findings from historical records states that the earthquakes that influence
Peninsular Malaysia originated from two earthquake faults: Sumatran subduction zone and
Sumatran fault. With the short gap of earthquake events in Sumatra, there is a big possibility
for moderate to high earthquake to occur in Malaysia. Seismic risk studies is important prior to
the construction of vital facilities even though the structures are situated in low-seismicity
regions that are dominated by large-magnitude and distant earthquakes. Although there is
no large earthquake has ever happened in Malaysia, it is very important for authorities and
owners of buildings to have awareness on the possibilities of large earthquake events in
Malaysia in the future.
References
Adnan, A. and Irsyam, D. 2002. The Effect Of The Latest Sumatra Earthquake To Malaysian
Peninsular. Jurnal Kejuruteraan Awam (Journal Of Civil Engineering), 15 (2),
Balendra, T., Lam, N. T. K., Wilson, J. L., and Kong, K. H. 2002. Analysis of long-distance
earthquake
tremors and base shear demand for buildings in Singapore. Engineering Structures,
Vol. 24, No.1, pp 99-108.
Balendra, T. and Li, Z. 2008. Seismic Hazard of Singapore and Malaysia. Electronic Journal
of Structural Engineering Special Issue,
Department of Mineral and Geoscience Malaysia, 2008, The Seismotectonic Map of
Malaysia
(3rd eddition), Mesy.Kumpulan Kerja Geodetik Bil 1/2008, Jupem, Kuala Lumpur.
Ghobarah , A. and Said, A. 2002 Shear-strengthening of beam-column joint. Journal of
Engineering Structures , 24 (1), p.881-888.
Hamilton, W. B., 1979, Tectonics of the Indonesian region, U.S. Geological Survey Professional
Paper 1078, 345 pp.,
Huang, L. 2013. Seismic risk study of a low-seismicity region dominated by large-magnitude
and distant earthquakes. Journal of Asian Earth Sciences, 64 (1), pp. 77-85.
Kanamori, H. and E Brodsky, E. 2004. The physics of earthquakes. Reports on Progress in
Physics, 67 (1) pp. 1429-1496.
Li, B. and Pan, T. 2004. Seismic Performances Of Reinforced Concrete Frames Under Low
Intensity Earthquake Effects. 13th World Conference on Earthquake Engineering,
(3402),
Mohamed, A. 2012. Monitoring Active Faults in Ranau, Sabah Using GPS *. Nineteenth
United Nations Regional Cartographic Conference for Asia and the Pacific.
SEMINAR BENCANA ALAM 2013
45
Otani, S. 2013. Lessons Learned From Past Earthquakes.
Delfebriyadi. Seismic Hazard Assessment Of Kuala Lumpur Using Probabilistic Method.
2011. Malaysian Journal of Civil Engineering, 23 (2), pp. 39-53.
Zaini Sooria, S., Sawada, S. and Goto, H. 2012. Proposal for Seismic Resistant Design in
Malaysia: Assessment of Possible Ground Motions in Peninsular Malaysia. Annuals
of Disaster Prevention Research Institute, (55 B), p. 81.
Petersen, M., Hamsen, S., Mueller, C., Haller, K., Dewey, J., Luco, N., Crane, A., and Rukstales,
K., 2008. Documentation for the Southeast Asia Seismic Hazard Maps.
U.S Geological Survey, 2008. Seismic Hazard Map of Western Indonesia
SEMINAR BENCANA ALAM 2013
46
THE IMPACT OF TROPICAL CYCLONES IN THE WESTERN PACIFIC OCEAN AND SOUTH CHINA SEA
ON THE RAINFALL IN MALAYSIA
Munirah Binti Ariffin and Subramaniam Moten
Research Section,
Malaysian Meteorological Department,
Ministry of Science, Technology and Innovation (MOSTI),
Jalan Sultan, 46667, Petaling Jaya,
Selangor, MALAYSIA.
ABSTRACT. Tropical cyclones (TCs) are intense synoptic systems that significantly modifies the
basic atmospheric state through the entire troposphere. This has a strong influence on the
regional rainfall pattern, even to countries that are not directly on the path of these
cyclones. The Malaysian region is in close proximity to one of the most active cyclogenesis
region in the world, that is the West North Pacific (WNP) and the South China Sea (SCS)
region. This region has the highest number of tropical cyclones globally with an average of
27 cyclones per year, with nearly half of them reaching typhoon intensity. September has the
highest number of tropical cyclones with an average of 5.4 cyclones occurring in a year,
while February records the lowest number of tropical cyclones. In this study 57 years of
tropical cyclone data from the Regional Specialized Meteorological Centre (RSMC) - Tokyo
and rainfall data for the same period from selected principal meteorological stations in
Malaysia is used to study the impact of tropical cyclones on the rainfall in three Malaysian
regions; Sabah, Sarawak and northwestern Peninsular Malaysia. The probability of rainfall at
different stages of the cyclone and their location in the WNP and SCS reveals that the rainfall
has a higher probability of occurrence when the cyclone is in the open sea, whereas over
northwest Peninsular Malaysia it is during landfall or close to the Indochina coast the
probability is higher. When the TCs are in the SCS, Sarawak has a higher chance of getting
rain than when the TCs are in WNP. Though the chance of receiving rain when TCs are
located in WNP or SCS is more than 70 percent, but there is less than 40 percent chance of
getting heavy rain (>10mm). For Sarawak and northwestern Peninsular Malaysia when the
TCs are located in the SCS the chance of rain increases as the TC category increases from
depression to typhoon stage. For Sabah when the TCs are located in WNP, the probability of
rain is higher when the TCs are at the tropical storm stage as compared to other stages.
KEYWORDS. Tropical cyclones, cyclone’s intensity, rainfall distribution and rainfall probability.
Introduction
Frequency of occurrences of tropical storms varies widely within the globe. The Western
North Pacific Ocean (WNP) and South China Sea (SCS) is the most active basin for tropical
storms genesis (Figure 1), while there is almost no activity in the Atlantic Ocean south of the
equator. Typhoons are three times as likely to develop in the WNP Ocean compared to any
other area in the world (Ramage,1959). Climatologically, tropical storms frequency in the
WNP is higher than any other basin, with an annual mean of 26 based on 22-year statistics
from 1968 to 1989 (Neuman, 1993). The main contributing factors are; i) the warmer sea
surface temperature (SST) over the Western Pacific and SCS, which is typically greater than
28°C for most part of the year and is the key driver of tropical storm formation (Trentberth,
2007). ii) The WP is a large basin; so any formation of tropical storm (TS) can have enough
time to intensify from a tropical depression to typhoon.
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Figure 1: Map of all global tropical storm tracks from 1945 to 2006 (Source: Wikipedia)
The presence of tropical storms in WNP or SCS, will alter the regional tropospheric synoptic
circulation patterns, impacting the weather over the Asian monsoon region in the short term,
depending on the stage of the storm intensity and location. Kumar and Krishnan (2005)
analyzed 56 years of storm track data and daily global wind data and they found that large
scale circulation anomalies associated with the inter-annual variability of the Indian monsoon
play an important role in influencing the tropical cyclone activity. Their study revealed that
during weak monsoon years the cyclogenesis over west Pacific is about 33 percent higher
compared to strong monsoon years. Rajeevan (1993) found that the Indian summer
monsoon rainfall and the number of typhoon days in the NW Pacific are negatively
correlated. The planetary circulation pattern will also be perturbed depending on the
duration and intensity of the storm, which will influence the seasonal weather on a much
larger scale. Conversely, large-scale circulation anomalies may also significantly affect the
formation and tracks of cyclonic disturbances in the west Pacific. One of the most studied
relationships is between TC activity and the El Nino Southern Oscillation (ENSO) phenomenon.
Studies by Chan (1985, 2000) shows that the year following a large negative Southern
Oscillation Index (SOI) there is an overall reduction in TC frequency over the WNP and vice
versa. Kimberlain (1999) found that the life cycle of tropical storms and typhoons in the WNP
is nearly 1.5 times longer during El Nino years as compared to La Nina Years.
Latitudinal strategic location of our region confined between equator and 8°N keeps
Malaysia from being vulnerable to the direct impact of tropical storms except on three
occasions, namely; in December 1996 (TS Greg), January 1999 (TS Hilda) and December 2001
(TS Vamei), where TS formed off the Malaysian coast in the South China Sea. TS Greg made
landfall over Sabah and Vamei was the most unusual and unique tropical storm to develop
so close to the equator (1.5°N) and moved across southern Peninsular Malaysia. Tropical
storms rarely develop within 5° of the equator since within this region coriolis force is
negligible, a force that is required for the initiation of cyclonic flow. TS Vamei is thought to
have being maintained by cyclostrophic balance. Although Malaysia is spared from the
direct hit by tropical storms, except for the two occasions in known historical records, but
presence of TCs in WN Pacific and South China Sea influences the synoptic circulation over
the region which has an indirect impact on the weather over Malaysia. The objective of this
study is to examine the impact, the storms intensity and position has on the rainfall over
different parts of Malaysia, in particular the states of Sabah and Sarawak in East Malaysia
and Northwest Peninsular Malaysia.
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Data
Data used for this study include tropical storms best track data (1951 - 2007) obtained from
Regional Specialized Meteorological Centre (RSMC) - Tokyo. RSMC - Tokyo is a WMO
designated center that monitors, issues advisories, warnings and forecasts about tropical
storms in its designated area of responsibility that extend eastward of 100°E to the dateline
and from equator to 60°N. The RSMC best-tracks data contain six-hourly tropical storm
information including the storms position (latitude and longitude), storm's central pressure
(SCP), 10-minute maximum sustained wind speed (MSWS), and the different stages of the
storms intensity. For the earlier years from 1951 to 1976 neither the MSWS nor the storm
intensity are included. Only tropical depressions (stage 2) and extra-tropical storms (stage 9)
are reported.
Daily rainfall data from fourteen main meteorological stations in Malaysia for the same
period are used in this study. The locations of these stations, five in Sabah, four in Sarawak
and five in Northwestern Peninsular Malaysia (NPM) are shown in Figure 2.
Figure 2: Locations of rainfall stations used in this study
Estimation of TC Stage from Storm’s Central Pressure (SCP)
To determine the different stages of the tropical storm for the period before 1977 the MSWS
needs to be estimated from the central pressure. Regression analysis performed on the data
from 1977 to 2007 depicted a second order polynomial relationship between the MSWP and
SCP (Figure 3) with an R2 of 0.93. An examination of the scatter plot of MSWS against SCP
shows a large spread in the data which by visual analysis would not indicate a good
relationship. MSWS are reported in increments of 5 knots and the frequency distribution of the
data for a particular MSWS and a particular SCP which in this case we have chosen 65 Kts
and 970 hPa respectively (Figures 4a and 4b) shows that a very large percentage of the
data actually lies on the line of best fit, thus giving a very high correlation.
SEMINAR BENCANA ALAM 2013
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(a) (b)
Figure 3: Relationship between MSWP and SCP based on 31 years of data from 1977 to 2007
Figure 4: Frequency distribution of 65 knots of MSWS (a) and 970-hPa of SCP (b)
Using this relationship, the MSWP for the period 1951 to 1976 is computed and hence the
different stages of the tropical storm intensity are determined using the WMO criteria of
tropical storm intensity classification as given in Table 1.
Table 1: MSWS and tropical storm Intensity
MSWS SCP Storm Stage
Less than 35 knots Greater than 999 hPa Tropical Depression (TD)
Between 35 knots and 45 knots Between 985 hPa and 999 hPa Tropical Storm (TS)
Between 46 knots and 64 knots Between 970 hPa and 985 hPa Severe Tropical Storm (STS)
Greater than 65 knots Less than 970 hPa Typhoon (TY)
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Nu
mb
er o
f TC
(p
er y
ear)
TC Climatology in the Western North Pacific Ocean and South China Sea
In the WNP and SCS, on the average about 27 TC forms in a year, and about half of them
reach typhoon intensity. The average number of TC per year for each of the calendar
months in the WNP and SCS is shown in Figure 5. TCs are most active between the months of
July and October, where on average 18 TC occurs during this four months accounting for
about two thirds of all TC in a year. September records the highest number of TC with an
average of 5.4 TCs.
Month
Figure 5: Average number of TCs in WNP and SCS based on 57 years of data (1951 - 2007).
The full bar (red and blue) indicates TC of intensity TS or higher and the blue portion indicates
TC of typhoon intensity. The number shows percentage of TCs that attained typhoon
intensity.
TCs are least active between January and April, where on the average about 17 TCs occurs
in 10 years. February is the month with the lowest TCs recorded, where only 2 TCs are
expected in 10 years. During northern spring and fall seasons, that is April-May and
September to November, more than half of the tropical storms will reach typhoon stage, with
October being the month having the most number (61%) of tropical storms reaching typhoon
intensity.
The formation, intensification and movement of TC in the WNP and SCS are very much
influenced by the large-scale circulation pattern established by the monsoon (Elsberry, 2004)
and the north-south progression of the monsoon trough. The TC climatology by month
showing the position and the different stages of TC from 1951 to 2007 is shown in Figure 6.
SEMINAR BENCANA ALAM 2013
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Figure 6: Monthly variation (January to December) of tropical cyclone track. Data from 1951
to 2007.
It is evident that during the late boreal winter months; January to March, when the monsoon
or near-equatorial trough is generally located south of the equator, few cyclones develop in
the WNP. However, occasionally when there exists a double near-equatorial trough,
cyclogenesis takes place in the WNP between about 5°N and 15°N and the storms generally
track westwards and very few intensify to become typhoons.
In the inter-monsoon season, April to May, more cyclogenesis can be seen over South China
Sea but seldom making landfall over Indochina. With the onset of the northern hemisphere
summer in June, the monsoon trough extends towards the latitude of maximum sea surface
temperature. TC activity over SCS also increases and by this time, many of them start to
make landfall over Indochina. As the summer monsoon advances poleward over East Asia
through August, the eastern anchor of the monsoon trough over Western North Pacific is also
displaced poleward. Formation of the typhoons are more concentrated over the WNP
compared to SCS, and many of these cyclones recurve and make landfall over Japan or
dissipate over the cold waters in the higher latitudes. Southward retreat of the summer
monsoon over East Asia during September to October is also accompanied by the
equatorward displacement of the WNP monsoon trough.
SEMINAR BENCANA ALAM 2013
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During November to December the monsoon trough extends from the western Pacific,
between 5°N and 10°N, to southern South China Sea, between equator and 8°N. In
consonance with the equatorward displacement of the trough, the TC activity too gets
shifted equatorward and closer to the Malaysian region. During this period some of the
storms moves westwards from the South China Sea to the Bay of Bengal.
Method of Analysis
The 57 years of data from 1951 to 2007, classified into four stages according to their intensity
namely; Tropical Depression (TD), Tropical Storm (TS), Severe Tropical Storm (STS) and Typhoon
(TY) respectively are grouped into boxes of 2.5° X 2.5° for the region bounded by 5°N and
30°N and 100°E and 140°E (Figure 7).
Figure 7: Region of analysis
Initial analysis to determine the impact on Sabah’s rainfall according to the SCP not too far
from Sabah showed poor correlation (Figure 8). This analysis shows that during the initial
stages of the storm development the rainfall amount can vary significantly, but as the storm
strengthens the rainfall decreases when storms are located in this particular area of the WNP.
Figure 8: Relationship between Sabah rainfall and SCP for storms
located west of the Philippines (Region B in Figure 7)
SEMINAR BENCANA ALAM 2013
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In order to provide a more meaningful interpretation of the impact of TS based on their
intensity as well as their location in the WP or SCS, the probability of occurrences of rainfall for
different parts of the country, namely; Sabah, Sarawak and Northwest Peninsular Malaysia
(NPM) are computed for different amounts (> 0.0 mm, > 5.0 mm and > 10.0 mm). Probability
of rainfall is computed for each box when the total number of TCs at the referenced stage
exceeds seven. In addition, when the TCs are located in Region C and Region D, the
probabilities of occurrence of rainfall for different threshold amounts from 0.0 mm to 35.0 mm
at intervals of 5.0 mm are computed.
The Impact of TCs at Different Location on the Rainfall in Malaysia
For the case when the tropical storm has attained the stage of TS or higher and its impact on
the rainfall for Sabah, Sarawak and Northwestern Peninsular Malaysia (NPM) are shown in
Figures 9a, 9b, and 9c respectively.
Figure 9a and 9b: Percent chance of Sabah (left) and Sarawak (right) getting rain when
TS/STS/TY is located in their respective boxes.
It is evident that when the storms are over
the open sea, the chances of Sabah
getting rain is more than 80 percent which
decreases to between 60 and 80 percent
when the storms make landfall. For
Sarawak there is more than 80 percent
chance of rain when the storm is over
central SCS and southern Philippines. When
the storms make landfall over the China
Coast, the percentage chance of rainfall
reduces to about 50 percent. The
Northwestern Peninsular Malaysia has more
than 80 percent chance of rain when the
storms are off the Vietnam coast or during
landfall over Indochina. When the storm is
over the Gulf of Thailand there is a 70
percent chance of rain, but when it is
further to the east, over central SCS there is
only a 50 percent chance of rain in
Northwestern Peninsular Malaysia.
Figure 9c: Percent chance of NPM getting rain when
TS/STS/TY is located in their respective boxes
(a) (b)
(c)
SEMINAR BENCANA ALAM 2013
55
Figure 10: Percent chance of Sabah getting rain when TD (left) and TY (right) is located in their
respective boxes.
Analyses are carried out for different stages of TS, different rainfall amounts, and at different
positions of TCs. When a TD is located over SCS or WP there is more than 80 percent chance
Sabah will get rain, which decreases to about 70 percent when TD is over the land, that is
when the storm has made landfall and weakened to a TD. When a storm close to Sabah
intensifies, the chances of heavy rain increases (Figure 10).
Figure 11: Percent chance of Sarawak getting rain when TD (left) and TY (right) is located in
their respective boxes.
When TD are located south of 15°N there is more than 70 percent chance of Sarawak getting
rain, which decreases when TD is located north of 15°N. When a storm north of Borneo
intensifies the chances of heavy rain over Sarawak also increases, but the chances are
higher over Sabah (Figure 11).
SEMINAR BENCANA ALAM 2013
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Figure 12: Percent chance of Northwestern Peninsular Malaysia getting rain when TD (left) and TY
(right) is located in their respective boxes.
Figure 13: Percent chance of Northwestern Peninsular Malaysia getting rain when STS (left) and TY
(right) is located in their respective boxes.
When a storm in the SCS intensifies from TD to TS, the probability of heavy rain over NPM decreases
(Figure 12). There is more than 80 percent chance of rain when TD is located or moving inland over
Indochina, but if it is south of Cambodia the chances are 50 to 60 percent. When the TS is over the
WP the chances of rain over NPM increases when TS intensifies to STS (greater than 60 percent), but
decreases when STS intensifies to a TY (less than 55 percent, Figure 13).
Probability of Rainfall at Various Threshold Amounts for Different TC Intensities
The impact of TCs when it is located in the SCS or WNP is examined by way of looking at the probability of occurrences of rainfall exceeding certain threshold amounts, which in this case we have taken from 0.0 mm to 35.0 mm at intervals of 5.0 mm. The probability of rain at different thresholds for the three regions when the TCs are located in the SCS (Region C) and WNP (Region D) are shown in Figures 14 and 15 respectively.
SEMINAR BENCANA ALAM 2013
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Figure 14: Probability of rain over Sabah (left), Sarawak (middle) and Northwestern Peninsular (right) for
eight threshold amounts of rainfall for different storm intensities when TCs are located over the SCS
(Region C in Figure 7).
Figure 15: Probability of rain over Sabah (left), Sarawak (middle) and Northwestern Peninsular (right) for
eight threshold amounts of rainfall for different storm intensities when TCs are located over the WNP
(Region D in Figure 7).
a) Impact on Sabah
When the storm is in the SCS and is at the depression stage, there is an 80 percent chance of
Sabah receiving rainfall which increases to over 90 percent when the TCs are at the TS or
Typhoon stage. For greater thresholds of rainfall at increments of 5mm, the probability of rain
drops exponentially and for heavy rain (> 10mm) the probability of rain decreases to about
30 percent. At all thresholds the chance of rain when the TC is at the severe tropical storm
stage is slightly higher than when the TC is at other stages. The same is true when the TCs are
in the WNP where there is an 80 to 90 percent chance of rain, and drops exponentially for
higher thresholds. For all thresholds up to 25 mm, when the TCs are at the tropical storm stage
the probability is higher compared to other categories by about 10 to 15 percent.
b) Impact on Sarawak
For Sarawak the probability of rain ranges from 70 to 90 percent when the TCs move from
the depression stage to the typhoon stage. For higher thresholds of rainfall the probability of
rain decreases exponentially. For rainfall thresholds up to 30mm the probability of rain
increases when the TCs intensified from depression to typhoon stage. A similar pattern is
observed when the tropical cyclone are located in the WNP, however unlike when the TCs
are located in the SCS, here the different stages of the TC has no significant influence on the
probability of rainfall occurrences.
SEMINAR BENCANA ALAM 2013
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c) Impact on Northwestern Peninsular Malaysia (NPM)
The percentage chance of rain for NPM follows closely to that of Sarawak when the TCs are
in the SCS. For rainfall thresholds of up to 10mm the probability increases with TC intensity. The
difference is about 20 percent going from depression to typhoon category. When the TCs
are in the WNP, the percentage chance of rain is about 70 percent and decreases
exponentially for higher thresholds of rainfall. For all categories of TC the percentage chance
of rain is nearly the same, unlike when the TCs are in the SCS. Also, when the TCs are in the
SCs the probability of rain is higher than when the TCs are in WNP.
Conclusion
The WNP and SCS region is one of the most active regions for tropical cyclone genesis, with
an average of about 27 cyclones in a year occurring over these region, with nearly half of
them reaching typhoon intensity. The boreal summer months and early autumn are the most
active period, with September recording the highest number of TCs at an average of 5.4 TCs
of which more than half will intensify to typhoon stage. The boreal winter months are the least
active period for TCs, with February recording on average two tropical cyclone in ten years.
The presence of these tropical cyclones in the WNP and SCS region has a profound impact
on the rainfall over Malaysia. The impact studied here in terms of probability of rainfall
occurring over three regions in Malaysia, i.e., Sabah, Sarawak and Northwestern Peninsular
Malaysia shows that when the cyclones are over the open sea there is a higher chance of
Sabah getting rain than when the storm makes landfall. For Sarawak when the cyclones are
over the central SCS the chances of rain are high and when the storms make landfall the
chances of rainfall reduces to about 50 percent. In the case of Northwestern Peninsular
Malaysia, when the storms are off the Vietnam coast or making landfall, the chance of rain is
high. There is also some difference in the percent chance of rainfall for all these three regions
when the tropical cyclones are at the different stages of development. Generally it is noted
that all three regions has a high chance, more than 80 percent for Sabah and Sarawak and
more than 70 percent for Northwestern Peninsular Malaysia, of getting rain. For higher
intensities of rainfall the probability of rainfall decreases exponentially, and for heavy rainfall
(> 10.0 mm) the percent chance is about 30 percent on the average.
Acknowledgements
We would like to thank the staff of Research Section for their technical support. We are
particularly indebted to Mr. Tan Kah Poh from the Climate Division for his invaluable
assistance in preparing the rainfall probability maps.
References
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Niño/Southern Oscillation phenomenon. Mon. Wea. Rev., 113, 599–606.
——, 2000: Tropical cyclone activity over the western North Pacific associated with El Niño
and La Niña events. J. Climate, 13, 2960–2972.
Elsberry, R. L. 2004. Monsoon Related Tropical Cyclones in East-Asia. Chapter 13. East Asian
Monsoon (C. -P. Chang, Ed.) World Scientific Press, Singapore, 463-497.
SEMINAR BENCANA ALAM 2013
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Kimberlain, T. B. 1999. The effects of ENSO on North Pacific and North Atlantic tropical
cyclone activity. Proceedings of the 2nd Conference on Hurricanes and Tropical
Meteorology, pp. 250-253. Boston: American Meteorological Society.
Kumar, V., and R. Krishnan. 2005. On the association between the Indian summer monsoon
and the tropical cyclone activity over northwest Pacific. Current Science Association,
Bangalore. Vol. 88, No. 4, pp. 602-612.
Neuman, C. J. 1993: Global overview: Global guide to tropical cyclone forecasting. pp. 1.1-
1.56. Geneva. World Meteorological Organization.
Rajeevan, M., Inter-relationship between NW Pacific typhoon activity and Indian summer
monsoon on inter-annual and intra-seasonal time-scales. Mausam, 1993, 44, 109-111.
Ramage, C. S. 1959. Hurricane Development. Journal of Meteorology, vol. 16, pp. 227-237.
Trenberth, K. E. July 2007. Warmer oceans, stronger hurricanes. Scientific American Inc,.
SEMINAR BENCANA ALAM 2013
60
SEISMIC PERFORMANCE OF 3-STOREY TUNNEL FORM SYSTEM BUILDING WITH DOUBLE UNITS
SUBJECTED TO LATERAL CYCLIC LOADING
A. A SHAMILAH, N. H ABDUL HAMID & S. MD SALLEH
Faculty of Civil Engineering, Universiti Teknologi MARA, 40450 Shah Alam, Selangor, Malaysia.
Corresponding author : [email protected]
ABSTRACT. A one-third scale of double unit 3-storey reinforced concrete tunnel form building
(TFB) is investigated. A set of 3-storey reinforced building together with foundation beam are
designed, constructed and tested under quasi-static reversible in-plane lateral cyclic
loading. This building is tested from ±0.01% drift until ±1.0% drift with an increment of 0.25%
drift. The shear wall of tunnel form system started to crack at -0.25% (pulling) drift on wall-slab
(wall 1) connection of the first floor. More cracks occurred as the increment of drift on wall
surface and the connection. The diagonal crack found to form at +1.25% drift on the first and
second floor outer wall 3. The diagonal crack also occurred on the second floor of the outer
wall 1. The maximum in-plane lateral loading recorded for this specimen was 71.84KN at
+1.0% drift. The ductility of TFB obtained from this experiment result is μ = 4.8 which is still in the
range 3 to 6. This showed that TFB performed well under long distant earthquake for minor to
moderate.
KEYWORDS. Tunnel form building system, lateral strength, ductility, stiffness, equivalent viscous
INTRODUCTION
Earthquake is considered as the major causes of fatalities and destroy the properties when its
strike certain area. The major damage caused by past decades earthquakes in Japan,
Taiwan, Iran, China and Italy gives a greater impact on high rise building in urban areas.
These phenomena have spurred many researchers to investigate the performance of high
rise building under seismic motion. (Ionut and Gabriela, 2010). Most of the countries which
are experiencing high intensity of the earthquake had been practicing seismic code since in
1988. Researchers are still investigating the new technology till nowadays in order to increase
the resilience of building structure under earthquake event.
In Malaysia, most of the buildings were designed according to BS8110 which has no provision
for seismic loading. This is because Malaysia is located far away from the most active fault
line in the world. The occurrence of Sumatra Earthquake on 26 December 2004 with a 9.2
scale Richter which triggered a devastating tsunami give a major impact to the west of
Malaysia. Frequent earthquakes have a significant impact on the medium and high rise
building in Malaysia.
Malaysia is still considered as a low seismic region based on earthquakes history. However this
condition cannot be neglected because Sabah had experienced partial damages of
reinforced concrete building within seismic magnitude 4.3 Scales Richter. These levels of
damages indicate that the overall performance of a structure which has been designed
using BS8110 could not sustain under low magnitude of seismic loading. If any unpredicted
earthquake happened within 300km from the epicenter to Malaysia, a major collapse of a
building may occur. This has happened because these buildings were not designed
according to current seismic code of practice. Therefore, it is important to study and identify
the seismic behaviour under Malaysian building design specification.
Malaysia has experienced long-distant earthquake which has caused substantial damage to
the several buildings in this country. Due to this reason, the structure performances under
long-distant earthquakes started to get the more concern and attention from the researcher.
(Taksiah et al., 2007). Moreover, frequent earthquakes which occurred in Sumatra have
SEMINAR BENCANA ALAM 2013
61
significant impact on the medium and high-storey reinforced concrete building in Malaysia.
Currently in Malaysia, the IBS method has become the selection for construction industry
especially for high rise building in urban areas. Most of apartment, condominium, offices and
the hotel used tunnel form building system as their construction method.
Tunnel shear wall in the building should have enough strength and capacity to carry the
design loads which come from vertical (gravity load) and horizontal load (wind, landslide
and earthquake loading). It is important for designer and engineer to use the appropriate
strength of concrete and percentage of reinforcement bars in designing and constructing
tunnel shear walls (Garcia and Sozen, 2004). Besides that, RC shear walls should have
enough ductility to avoid brittle failure in order to withstand the greater lateral loading
(Satpute and Kulkarni, 2013). Since tunnel form building system is populated by a high
density of residential, thus the effect of earthquakes on this typical of the building will give a
greater impact. Therefore, the study of tunnel form building performance under earthquake
excitations should be highlighted.
Seismic performances of tunnel form buildings have been observed during earthquakes (Mw
7.4 at Kocaeli and Mw 7.2 at Duzce) in Turkey in 1999. These earthquakes struck the most
populated areas and caused substantial structure damage, casualties and economic loss
(Balkaya and Kalkan 2004). There is a very limited study regarding performance of tunnel
form building under a long-distant earthquake in Malaysia. Thus, this study will fulfill the need
to determine the behavior of tunnel form building system under seismic excitation.
The main objective of this study is to investigate the performance of tunnel form building
system under in plane lateral cyclic loading through experimental work. The seismic
performance of the specimen was evaluated by studying its behavior in relation to strength
reduction, ductility, stiffness and equivalent viscous damping (EVD). Moreover, the damage
patterns obtained during the experimental work also will be discussed in this paper.
METHODOLOGY
In this study, a double unit 3-storey of tunnel form building system have been designed,
constructed and tested under in-plane lateral cyclic loading. The testing is conducted using
lateral cyclic loading machine. The specimen is scaled down to the one third (1/3) from the
actual size due to the limited of working space. The size and dimension of tunnel form
building as shown in Table 1.
Table 1. Dimension and Size for Specimen
Items Description Actual Size Prototype Specimen
1. Foundation* Width = 5850 mm
Length = 4000 mm
Thickness = 500 mm
Width = 2250 mm
Length = 1750 mm
Thickness = 400 mm
2. Shear Wall Height = 2800 mm
Length = 3600 mm
Thickness = 150 mm
Height = 930 mm
Length = 1200 mm
Thickness = 50 mm
3. Slab Width = 2700 mm
Length = 3600 mm
Thickness = 150 mm
Width = 900 mm
Length = 1200 mm
Thickness = 50 mm
* Foundation was not constructed for one third (1/3) scale because to provide a sufficient
size for locating the wall and provide a base of structure for testing on lateral cyclic loading.
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There were three important stages that involved in this study; design and analysis of 3-storey
tunnel form building system with double units according to British Standard (BS8110),
construction of the specimen and setup instrumentation for testing. The material properties
used in the design and construction as tabulated in Table 2.
Table 2 . Material Properties for Design and Construction for Specimen
Items Material Description Properties
1. Concrete Strength
(a) Foundation
(b) Shear Wall and Slab
40 N/mm2
35 N/mm2
2. Steel Reinforcement Strength
(a) Foundation and Deep Beam
(b) Shear Wall and Slab
460 N/mm2
250 N/mm2
3. Aggregate Size
(a) Foundation and Deep Beam
(b) Shear Wall and Slab
20 mm
10 mm
The detail of drawing for the prototype specimen is provided to be a guideline for the
construction as shown in Figure 1.
Figure 1. The scale down prototype specimen.
As the design included the criteria loading as mention earlier, the detailing of reinforcement
is demonstrated in Figure 2. For the construction of slab panel, the reinforcement of mild steel
with size 6mm has been used for both directions of span. The spacing is provided between
bars will be 100mm. The detail of reinforcement has been applied to the whole floors except
for the top floor. The concrete strength of 35 MPa has been adopted for the slab structure.
The size aggregate limited to a size below than 10mm as to allow the space for mixing
concrete overflow to the slab panel area.
The wall panel has been constructed with size 1200 mm (width) x 930 mm (height) x 50 mm
(thickness). The wall is the main component of the structure to cater any loading from the
horizontal and vertical. For this construction of prototype building, the reinforcement of the
wall used is 8 mm diameter of mild steel and 80mm spacing within bars. The transverse bar is
located in a horizontal direction with similar size of bars 8 mm and 200 mm spacing between
bars. Figure 3 illustrates the arrangement of wall reinforcement that have been used in the
construction of the specimen.
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The primary data that should be provided for testing is the control displacement together
with the increment of drift. The drift is started from 0.01% with increment of 0.25% drift. In this
study, six sets of drift were applied to the top of 3-storey tunnel form building as shown in
Table 3. The graph of control displacement versus number of cycles is shown in Figure 4.
Table 3 . Displacement control for in-plane cyclic loading
Figure 4. Quasi static cyclic loading regime
Figure 5 shows the locations of linear variable differential transducer (LVDT) on the top of the
surface and side of the wall panel. In this study, six LVDTs were used to measure deflection,
rotation and average curvature of the wall when in-plane lateral loading was applied on top
of the wall. The in-plane lateral displacement of the specimen was monitored by LVDT
located on each floor of the specimen.
No. of Cycles Drift (%) Displacement (mm)
2 0.01 ± 0.31
4 0.1 ± 3.08
6 0.25 ± 7.69
8 0.5 ± 15.38
10 0.75 ± 23.06
12 1 ± 30.75
-1.5
-1
-0.5
0
0.5
1
1.5
0 2 4 6 8 10 12 14
Dri
ft(%
)
No. of Cycles
Figure 2. Detail drawing for slab
reinforcement
Figure 3. Detail drawing for wall
reinforcement
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Figure 5. Experimental set-up and location of LVDTs installed to the specimen.
EXPERIMENTAL RESULT
Visual Observation
From a visual observation during testing, the cracking was starting to occur at ±0.25% of drift.
The first crack was occurred on wall-slab of wall 1 with recorded loading is 25kN. The crack
was occurred in horizontal line which is the tension crack is occurring. The second crack was
occurred on the second floor of the outer wall 3. The third crack occurred on the first floor
inner wall at 0.5% (pulling). The similar crack has happened at every surface of the wall. The
major crack was happening at first floor level, the configuration and explanation were
focused on major crack at first floor level. The second floor was occurred similar as in first floor
level. The top floor was not suffering any cracks as it is free and unrestrained.
The hairline cracks occurred along the first floor of wall at 0.5% (pushing) drift. At the
right edge of the first floor wall, most of the cracks continuously occurred at ±0.75%, ±1.0% ,
and ±1.25% drift. Meanwhile, at the left edge of the same wall, the crack occurred at ±0.75%
drift as shown in Figure 6(a). Finally at the 1.25% (pushing) drift, diagonal crack started to form
on the middle of the second floor of the outer wall 1.
The crack pattern of wall 1 (outer) differs with wall 3 (outer). The crack started to occur at
0.75% (pulling) drift on the first floor outer wall 3. The crack started at the edge of both side
wall and connect at the middle of the wall and form the diagonal crack as shown in Figure..
On the second floor of the outer wall 3, the crack occurred at –0.75% drift, +1.0% drift and
+1.25% drift. The crack pattern similar with first floor (occurred at the edge of wall and across
to each other on the middle of wall). The diagonal crack occurred at +1.25% drift almost the
height of the second floor wall 3 as shown in Figure 6(b).
For the first floor 2, left hand side wall suffered much more cracks compared with the right
one. The crack started to occur at 0.5% (pushing) drift until 1.25% (pushing) drift. About 2
diagonals crack formed on the middle of wall located in the upper part and lower part
respectively on wall 2 (first floor). Both of the diagonal cracks found to be occured at the
1.25% (pushing) drift. At the middle wall, crack obtained from +0.5% drift seems to be
connected with crack obtained from ±0.75% drift along the wall as shown in Figure 6(c).
For the first floor wall 2 (right hand side), the crack started to occur at ±1.0% drift, +0.75% drift
and +1.25% drift. At the left edge of this wall, all of the cracks were obtained from +1.0% drift.
However, on the right edge of wall, the crack seems to be occurred at +0.75% drift and -0.1%
drift. Finally, a crack that occurred from +1.25% drift come across the +0.75% drift crack and
induce a diagonal crack at the middle of this wall as shown in Figure 6(d).
LVDT
1
LVDT 2
LVDT 3
LVDT 4
LVDT 5 LVDT 6
Hydraulic
Jack
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For the second floor wall 2 (left hand side), the cracks occurred at the right edge of wall at
1.0% (pushing) drift and 1.25% (pushing) drift. Meanwhile at the left edge of the same wall,
only 2 cracks were found to be occurred at ±0.75% drift. There is no crack at the middle of
this wall as shown in Figure 6(e). For wall 2, the second floor (right) suffered much more crack
compared with the first floor wall. The cracks occurred at ±0.75% drift, ±1.0% drift and ±1.25%
drift. The crack pattern of this wall is same with outer wall 1 and 3. The crack started to occur
on the edge of the wall. The crack propagated to the middle of the wall and formed the
diagonal crack at 1.25% (pushing) drift as shown in figure 6(f).
(a)
(b)
( c )
(d)
(e)
(f)
Figure 6. Crack pattern on (a) wall 1 (outer), (b) wall 3 (outer), (c) first floor of wall 2 (left), (d)
first floor of wall 2 (right), (d) second floor of wall 2 (left) and (e) second floor of wall 2 (right)
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Theoretically, the lateral force which applied to the center of the frame which is directed to
the center of wall 2 will result the maximum stress on wall 2 as compared with wall 1 and wall
3. The distribution of the load is uniformly to each wall by attaching the steel plate between
structure and hydraulic jack. Similarly with earthquake loading which was occurring in
uniform loading but not in concentrated load. For this case, the wall will take similar loading
and the performances of wall having maximum stress at free edge (wall 1 and wall 3)
compare than fully framing support (wall 2). It is observed that much more cracking
appeared on wall 1 and wall 3 surfaces as compared with wall 2 during testing.
Lateral Strength
During the experimental testing, tunnel form building system was imposed with the six sets of
drift. Each drift comprised two cycles to represent the first and second strike of the
earthquake event. This is because in earthquake event, normally there is an aftershock of an
earthquake. Full successive cycle consists of pushing and pulling phase. Pushing cycle was
represented in positive sign and pulling cycle represented in negative sign. In this study, the
displacement has been controlled in order to get the maximum lateral strength of the
specimen.
The lateral strength of the specimen was determined by plotting the hysteresis loop graph.
Figure 7 shows the load and the displacement pattern under push and pull direction. From
the plotted graph load versus displacement below, the maximum load found to be 71.84kN
at +1.0% (pushing) drift with 26.7mm displacement. At the starting drift (0.01%), the load is still
small because it is the initial time the structure is forced to deform. From the plotted graph,
lateral load and displacement increased as the drift increased. The increment of
displacement for each drift shows that once the force is increased the elongation also
increased.
Figure 7. Hysteresis Loops analysis of the specimen
Stiffness and Ductility
Stiffness can be defined as the extent to which a structure can resist loading with no
significant displacement. For the in-plane response of the 3-storey tunnel form building
system, it showed less flexibility and stiffer behaviour to high loads with low displacement. For
every drift that involved during testing the specimen was contributed to the differences of
elastic stiffness behaviour. Elastic and secant stiffness was depends on structural behave
-100
-80
-60
-40
-20
0
20
40
60
80
-30 -20 -10 0 10 20 30
0.01% Drift 0.1% Drift 0.25% Drift
0.5% Drift 0.75% Drift 1.0% Drift
Load
(KN
)
Displacement (mm)
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under control displacement or drift had been applied. The tabulated of elastic and secant
stiffness is demonstrated in Table 4 for pushing phase. Based on tabulated data, secant
stiffness found to be low value compare to elastic stiffness because the specimen is under
inelastic regions.
Meanwhile, Table 5 shows the elastic, secant stiffness and ductility for pushing phase of the
specimen. The elastic stiffness value obtained from pulling phase is much higher compared
to pushing phase. This indicated that the 3-storey tunnel form building system is much more
stiffened in pulling phase rather than pushing phase. Same goes to the ductility value from
pulling phase, it is found to be 0.59 higher than pushing phase obtained from 1.0% drift.
Table 4 . Elastic, Secant Stiffness and Ductility for Pushing phase
Drift (%)
Pushing
Displacement Elastic Secant
(mm) stiffness Stiffness Ductility
(kN/mm) (kN/mm)
0.01 0.5 5.54 - 0.08
0.1 2.3 5.69 - 0.41
0.25 5.64 11.03 - 1
0.5 13.68 - 2.18 2.43
0.75 19.84 - 3.14 3.52
1 26.7 - 2.69 4.73
Table 5 . Elastic, Secant Stiffness and Ductility for Pulling phase
Drift (%)
Pulling
Displacement Elastic Secant
(mm) stiffness Stiffness Ductility
(kN/mm) (kN/mm)
0.01 0.1 18.7 - 0.02
0.1 1.8 7.1 - 0.38
0.25 4.78 15.89 - 1
0.5 11.32 - 3.62 2.37
0.75 15.36 - 4.95 3.21
1 23.4 - 3.84 4.89
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Equivalent Viscous Damping (EVD)
Equivalent viscous damping (EVD) is a measurement of energy dissipated amount during the
load applied to the structure. In this study, the percentage EVD is calculated in 2 separate
loops that recognize first and second cycles. The EVD percentage is obtained from 0.1% drift
until 1.25% drift for both pushing and pulling phase. The calculation of equivalent viscous
damping is formulated in equation (1) as follows :
[(
) (
)] (1)
Where is;
Equivalent Viscous Damping
π Function for circular 3.142 in unit dimensions
ED Energy dissipated within the maximum triangle area
Eso Total Energy within trapezium area
Figure 8 shows the percentage of equivalent viscous damping (EVD) of 3-storey tunnel form
building system. From the graph, the maximum energy absorption comes from the first cycle
with 15.6% of EVD obtained from 0.25% drift and it dropped linearly until 0.5% drift. This
indicated that the amount of energy released from the structure and caused the
appearance of cracks and concrete sealing. But at the same drift (0.5%) the EVD started to
increase until 0.75% drift and stopped at 13.45%. EVD percentages for the second cycle
started at 6.60% at 0.1% drift and increased to7.28% at 0.25% drift. However, at 0.5% drift the
EVD dropped to 12.78% but increased until 1.0% drift with 11.57%. EVD value obtained from
the first cycle is higher than the second cycle. This indicates that the specimen required
much more amount of energy to resist the earthquake loading in the first strike compared to
the second strike.
Figure 8. Equivalent Viscous Damping versus Drift
0
3
6
9
12
15
18
0 0.2 0.4 0.6 0.8 1 1.2
1st cycle
2nd cycle
EV
D (
%)
Drift (%)
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CONCLUSION
This experimental study is to investigate the seismic performance of a 3-storey double unit
tunnel form building system subjected to in-plane lateral cyclic loading. The experiment was
conducted using load actuator machine within the displacement control. The first crack
started to occur at -0.25% drift with a maximum 24 kN on the wall-slab joint of wall 1 (first
floor). Then the crack continuously occurred until +1.25% drift and induce a diagonal crack.
The crack pattern on each wall surface started to crack at edge of length panel then
propagate until the middle of the wall panel. This behavior of the crack pattern showed that
failure of crack within maximum stress occurred at the edge surface. The crack was started
to propagate when the load and displacement is increased. The crack is also occurred on
the wall 1 and wall 3 rather than wall 2. This means that the most full supported edge will
suffer less displacement compared with the only half supported.
Ultimate lateral load obtained from 1.0% drift with 71.84kN and 26.7mm displacement for
pushing phase. Meanwhile, for the first negative cycle (pulling phase), the maximum loading
was observed to be 89.8kN from 1.0% drift with 23.4mm displacement. It differs 25.6% to each
phase (pushing and pulling) because at this stage the structure become to its original
position after the loading imposed to it. It means that the structure needs 18.4kN to come to
its unloading position. The hysteresis loop pattern can be concluded that the seismic
performance of the experimental prototype building of tunnel form building system is having
the yield loading and displacement at 0.25% drift within 62.26 kN and 5.64 mm respectively.
Based on stiffness analysis, elastic stiffness gives a greater value comparisons with secant
stiffness for almost each drift. This indicated that the tunnel form building is under inelastic
regions.
Meanwhile, the ductility behavior of the specimen is 4.8 which is remaining under 6. It means
that the ductility of this specimen is in the range of good performance of the seismic
response. For the equivalent viscous damping (EVD) analysis, the energy dissipated for the
first cycle is much higher compared to the second cycle. This is because during the first strike
of earthquake (first cycle) the specimen required more energy to resist the lateral loading as
compared to the second strike (second cycle).
Therefore, it can be concluded that tunnel form building system performed well under long
distant earthquake for minor to moderate. The major crack obtained from the ultimate load
is still under allowable crack which is less than 0.3 mm length as mentioned in clause BS8110:
part 1. Therefore, it is recommended that the tunnel form building system should be repaired
and retrofitted since it is under non-collapse behavior.
ACKNOWLEDGEMENTS
The author would like to thank the Research Management Institute (RMI), University Teknologi
MARA and Fundamental Research Grant Scheme (FRGS) for the funding this research work.
Nevertheless, the authors also would like to express their gratitude to the technicians of
Heavy Structures Laboratory, Faculty of Civil Engineering, UiTM for conducting this research
work successfully.
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REFERENCES
Azlan Adnan, Hendriyawan, Masyhur Irsyam. 2002. The Effect of the Latest Sumatra
Earthquake to Malaysian Peninsular. Journal of civil engineering, Vol. 15 No. 2.
Al-Aghbari, A., Hamzah, S.H., Hamid, N.H. and Rahman, N. 2012. Structural Performance of
two types of Wall Slab Connection Under Out-of-Plane Lateral Cyclic Loading,
Journal of Engineering Science and Technology, Vol. 7, No. 2, pp. 177-194.
Balkaya C. and Kalkan E. 2004. Seismic Vulnerability, Behavior and Design of Tunnel Form
Buildings, Engineering Structures 26(2004), 2081-2099.
British Standard. BS8110-1. 1997. Structural use of concrete-Part 1: Code of practice for design
and construction. BS8110-1:1997.(1997), London, UK, 172.
Garcia, L.E, and Sozen, M.A. 2004. Earthquake Resistant Design of Reinforced Concrete
Building, in Earthquake Engineering from Engineering Seismology to Performance-
Based Engineering book, edited by Yousef Bozorgnia and Vitelmo Bertero, CRC Press,
New York
Hamid, N. H., and Masrom, M. A. 2012. Seismic Performance of Wall-Slab Joints in
Industrialized Building System (IBS) Under Out-Of-Plane Reversible Cyclic Loading,
IACSIT International Journal of Engineering and Technology, Vol. 4, No. 1.
Ionut-ovioui Toma and Gabriela M. Atanasiu. 2010. Modern Trends In Experimental
Earthquake Engineering Research. Buletin of The Polytechnic Institute of IASI,
Technical University “Gheorge Asachi” of Tome LVI (LX), Fasc.
Satpute SG and DB Kulkarni. 2013. Comparative Study of Reinforced Concrete Shear Wall
Analysis in Multi-Storeyed Building With Openings by Nonlinear Methods. International
Journal of Structural and Civil Engineering Research, Vol. 2, No. 3.
Taksiah A. Majid, Shaharudin Shah Zaini, Fadzli Mohd. Nazari, Mohd. Rashwan Arshad and
Izatil Fadhilah Mohd Suhaimi. 2007. Development of Design Response Spectra For
Nothern Peninsular Malaysia Based on UBC 97 Code. The Institution of Engineers
Journal, Vol. 68, No. 4.
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Review of coastline changes due to erosion at Pantai UMT
W.B. Wan Nik
Department of Maritime Technology, Faculty of Maritime Studies and Marine Science,
Universiti Malaysia Terengganu, 21030 Kuala Terengganu, Terengganu
ABSTRACT. Marine ecosystem includes the area at the shoreline is the area which sensitively
reacts with any changes occur around it. The changes might affects either temporarily or
permanently. These changes include alteration in morphology, beach profile and contour.
Coastal development creates hazard which affects the natural environment such as erosion.
Reclamation of sand to form a runway for Sultan Mahmud Airport is an example of coastal
erosion due to man-made product. The aim of this study is to evaluate the changes of the
beach near Universiti Malaysia Terengganu (UMT). This study also provides a few ways to
overcome the problem. The study area was set from Sultan Mahmud Airport to Pantai
Mengabang Gelam which covers the coastline area of 3.4 kilometres. Visual observation was
done to the studied area to see the changes of coastline. It was found that the
development of the runway for Sultan Mahmud Airport has caused severe erosion along this
studied area. There is structural damage along this shoreline and the devastation has
affected socio economy of surrounding resident. This paper reports the erosion process
occurs along the coastline of Tok Jembal and UMT and the method applied to overcome
erosion.
KEYWORDS: erosion, coastal development, rock revetment
Introduction
Malaysia’s coastline is over 4,809 km where over than 1500 km of this coastline experiencing
corrosion. The number has increased up to 2327km presenting of increment in project
number from 47 sites to 74 sites in 2000 [1].
Construction of infrastructures at coastal areas may serve the economic development and
social needs. However the effect on coastal areas should be taken into consideration
because of the natural process interference. Erosion is an example of interference causes by
development of coastal areas. Erosion in Malaysia is in distressing stage where the number of
problem increased over the last 12 years [2].
Therefore, erosion prevention method and shoreline monitoring should be implemented as
an initiative to reduce this disastrous process. The aim of this paper is to show the coastal
area near Universiti Malaysia Terengganu that severely suffers because of the corrosion.
Observation at the coastal area was conducted to visualise the erosion process and
secondary was used to expect the future changes on the shoreline.
Method
Structural observation
Observation was conducted near coastal area of Sultan Mahmud Airport to Mengabang
Gelam which covers the coastline areas of 3.4 km.
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Result and Discussion
One week survey was conducted at coastal area of UMT on 2011 as shown in Figure 1. It
can be observed that there was no significant change on the beach within 4 days of
surveying and the zone is considering relict although it is near to Tok Jembal coastline. It is
believe that the long shore current carried sediment from erosion site and deposit at coastal
area of UMT thus form a relict zone.
Figure 1 coastline observation on 2011 (12 November 2011 – 21 November 2011)
The shoreline of the coast along Sultan Mahmud Airport to Mengabang Gelam is composed
of sandy materials. The sediments were easily erodible when facing an impact by the wave
and if not well protected. Figure 2 shows the coastal area at Universiti Malaysia Terengganu
where the photo was taken on 2012 and 2013. In the duration of 7 September 2012 to 9
January 2013, a massive change was observed at the coastal area. Student’s activity can
still be conducted on September 2012. However on the January 2013, the coastal area was
severely eroded.
Figure 2 massive changes of coastal area near UMT from September 2012 until January 2013
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Erosion process mainly divided into two categories namely as natural erosion and human-
induced erosion. Massive changes from September 2012 to January 2013 are a result of
structural development at Sultan Mahmud airport and ironically it causes direct effect to the
coastal area and few depositions at the surrounding area were found.
Figure 3 shows the effect on erosion towards the fisherman community where it can be
observed that the road was extremely damaged while Figure 4 shows severe erosion occur
at coastal area of Tok Jembal.
Figure 3 Extreme damages at the fisherman community
Figure 4 Severe erosion at coastal area of Tok Jembal
Figure 5 shows the rock revetment deployed at the coastline of Sultan Mahmud airport. The
implementation of this method to overcome the problem is suitable because of it consume
lower cost compare to the other method such as beach nourishment. However this method
reduces the aesthetic value and hence affects the tourism industry. Furthermore, there will
be serious erosion at the end of this revetment.
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Figure 5 Rock revetment installed at coastal area of Sultan Mahmud airport
Conclusion
It was found that structural development along coastline area has caused severe erosion
resulting in cost increment to overcome this problem. an active and progressive strategy
should be considered to conserve the coastline so that sustainable development of resource
at that particular area can be preserved. Therefore, development of coastal area should
come with the systematic effort to preserve coastal area and at the same time it can control
the rate of erosion.
References
A. Chalabi, H. Mohd-Lokman, I. Mohd-Suffian, Masoud Karamali, V. Karthigeyan, M. Masita
(2006), monitoring shoreline change using ikonos im age and aerial photographs: a
case study of Kuala Terengganu area, Malaysia, Proceedings of the ISPRS Commission
VII Symposium
'Remote Sensing: From Pixels to Processes', volume XXXVI Part 7, 1-6
E.C. Lee & R.S. Douglas (2012), Geotextile tubes as submerged dykes for shoreline
management in Malaysia, Geotextiles and geomembranes, 30, 8-15
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AN OVERVIEW OF WINDSTORM PHENOMENON IN PENANG STATE OF
MALAYSIA
F.A. Wan Chik*, T.A. Majid1,2,
S . N . C h e D e r a m a n 2 , M.K.A. Muhammad2
1Disaster Research Nexus, E n g i n e e r i n g Ca m p us , Universiti Sains Malaysia 14300 Nibong
Tebal, Penang, Malaysia 2School of Civil Engineering, Engineering Campus, Universiti Sains Malaysia, 14300 Nibong
Tebal,Penang, Malaysia.
ABSTRACT. During monsoon season, heavy rain and windstorm prone occurred in micro
scale and affected east coast of Peninsular Malaysia and East Malaysia. Aim of this
conducted pilot study is to review on the occurrence of strong wind and house damaged in
five districts in Penang. Data was collected in four years period from 2010 to 2013 for five
respective districts in Penang which acquired from Land and District Office, thus, all data
were analyzed. Meanwhile, the frequencies of heavy storm occurrence and number of
houses damaged have been obtained. Data comparison between every district in terms of
occurrence in month and year and number of damages were established from the plotted
graph. From the graph, the highest frequency of windstorm occurrence was found at
Northern Penang (SPU), with 538 cases was reported, and followed by Southern Penang
(SPS), with 50 cases, Central Penang (SPT), with 29 cases, South West Penang (BD), with 3
cases and the lowest occurrence at North East Penang (TL), with 2 cases. The highest
number of houses damaged was hampered in year 2012 at Northern Penang (SPU) with 243
number of houses, while, the least number of houses damaged occurred in year 2011at
North East Penang (TL) by only one house damage. The trend number of occurrence and
damaged also observed step up yearly due to the climate change and global warming
tendency. The important factor that may contribute to climate change is urbanization. This
study shows that windstorm is a phenomenon and must be considered in Malaysia. It is
important to note that a rise in severe windstorm events, thus, increase the damages and
losses and also human life.
KEYWORDS: Wind storm occurrence, frequencies, number of house damaged.
INTRODUCTION
Malaysia is a country with a tropical climate; whereby, the coastal plains which averaging
28°C, the inland and mountain averaging 26°C and the higher mountain regions
temperature at 23°C. Heavy rain and windstorm which take place during monsoon season
probably affected east coast and east of Malaysia. Malaysia Meteorological Department
(MMD) reported that windstorms are most likely to occur in the inter monsoon period in April
to May and October to November. According to Yusoff, (2005), occurrence of windstorm in
our country is in micro scale, with small size and short duration between 15 to 30 minutes. In
accordance, these passive conditions produce hail, heavy rain, frequent lightning and
strong gusty winds (Holmes, 2001). Severe windstorm associated with hail and wind gusts
may result in strong wind and can caused severe damages to extensive area. Low rise non-
engineered structure is very prone to the destruction due to strong wind. It was stated by
Majid et.al, (2012) that most of the house damage occurs in northern region on Peninsular
Malaysia. Aim of this conducted pilot study is to review on the occurrence of strong winds
and house damaged in five districts in Penang state from 2010 to 2013. Windstorms in
Malaysia must not be negligible since the occurrence has initiated damage and losses to
structures and human life and fatality.
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METHODOLOGY
Penang state is located in the northern region of Malaysia; the island portion is separated by
Straits of Malacca adjoining the mainland. There are five districts; two districts in island
portion and balance of three districts are situated in the mainland as shown in Figure 1. For
North East Penang (TL) and South West Penang (BD) are located in island meanwhile,
Northern Penang (SPU), Central Penang (SPT) and Southern Penang (SPS) are located in the
mainland accordingly.All data on occurrence of windstorm and house damaged were
collected from Land and District Office in Penang, were gathered and tabulated. Graph for
number of occurrence and number of houses damaged were plotted with reference to
month, year and districts. The discussions were based on the results obtained.
Figure 1: Districts in Penang state
RESULTS AND DISCUSSION.
Windstorm occurrences
The graph was plotted to determine the frequencies of windstorm occurrence in four years
with reference to month. Figure 2(a) shows the data for monthly windstorm occurrence for
Northern Penang (SPU) in 2010 to 2013. In four years data period, it shows that the highest
occurrence of windstorm was in March by 14 cases. Meanwhile the lowest windstorm event
was recorded in December with only two cases during the same data period. The result
shows the highest occurrence is due to the annual contribution of windstorm event. For
Central Penang (SPT), the frequencies of windstorm occurrence were shown in Figure 2(b)
for only three years data period. The graph denotes that there is no data recorded in 2010
due to some circumstances. Similar to Northern Penang (SPU), the highest windstorm
occurrence for Central Penang (SPT) occurred in March by 8 cases. For the month of May,
July, August September and October only once wind storm occurrence in 2012 strikes in
three years period. The graph trend also indicates that windstorm increase slightly in that
particular month. No wind storm occurrence was recorded in June, November and
December for Central Penang (SPT) during three years data period.
Figure 2(c) depicts the monthly windstorm occurrence for Southern Penang (SPS) in 2010 to
2013. The graph trend shows the number of occurrence increases with the increase of
month. The highest peak was observed in May which contributes from four years recorded
data simultaneously windstorm occurrence in the same month. In June, the graph start
decreasing whereby, 3 cases were recorded in 2011, 2012 and 2013 accordingly. However,
windstorm event stabilized for two months; July and August by 5 cases. Similar goes to
September and December by 2 cases. For October, windstorm only recorded in 2012 by 3
cases.
Figure 2(d) represents the monthly windstorm occurrence for North East Penang (TL) in 2010
North East
Penang South West
Penang
Northern Penang
Central Penang
Southern Penang
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to 2013. The slightest windstorm occurred at North East Penang (TL) as compared to other
four districts. In conjunction to the above, there is no windstorm event recorded in 2012 and
2013. Data monitoring for year 2013 is noted until July. However, only 2 cases were recorded
at North East Penang (TL) which is in March 2010 and May 2011. Figure 2(e) shows monthly
windstorm occurrence for South East Penang (BD) with regards to the data collections from
2010 to 2013. For 2010, there is no data available for windstorm. In 2011, windstorm only
occurred once in December, meanwhile, for 2012 it shows that windstorm occurred in June.
The same goes to 2013, windstorm only recorded in March by one case.
From the graph, the number of windstorm occurs in five districts in Penang within 4 years
time period; it shows that the highest number of windstorm occurs in March for SPU and SPT
while, in May for SPS. According to Malaysian Meteorological Department (MMD),
windstorm can occur throughout the year but most likely to happen in the inter-monsoon
periods, namely April to May and October to November. Over land, windstorm frequently
develop in the afternoon and evening hours while over the sea, windstorm is more frequent
at night.
(a) Central Penang (SPU) (b) Northern Penang (SPT)
(c) Southern Penang (SPS) (d) North East Penang (TL)
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(e)South East Penang (BD)
Figure 2: Windstorm occurrence in five districts of Penang State in 2010 to 2013
Meanwhile, Figure 3 shows the frequency of windstorm occurred in Penang state from 2010
to 2013. From the graph, highest number of windstorm occurred at Northern Penang (SPU),
with 538 cases, followed by Southern Penang (SPS), with 50 cases, Central Penang (SPT), 29
cases, South West Penang (BD) with three cases and the lowest number of windstorm
occurrence is at North East Penang (TL), with two cases during 2010 to 2013.
Figure 3: Frequency of windstorm occurred in Penang state from 2010 to 2013
Damaged of Houses
Graph illustrated in Figure 4 represent data for the number of houses damaged yearly with
regards to five districts in Penang state. In 2010, windstorm has affected three districts which
are Northern Penang (SPU), Southern Penang (SPS) and North East Penang (TL) respectively.
The highest number of house damaged in North East Penang (TL) is 136 houses, followed by
Northern Penang (SPU), 72 houses and Southern Penang (SPS) with 29 houses reported. Four
out of five districts struck by the windstorm in 2011 namely, Northern Penang (SPU), Central
Penang (SPT), Southern Penang (SPS) and South West Penang (BD). It was recorded that the
total number of houses damaged at Northern Penang (SPU) is 193, 77 houses in Southern
Penang (SPS), 72 houses in South West Penang (BD), 29 houses in Central Penang (SPT) and
one house damaged in North East Penang (TL). Further, the graph shows in year 2012 was
the worst year affected by windstorm, total figure out 400 houses damaged. Northern
Penang (SPU) was badly affected by windstorm whereby 243 number of houses damaged,
Southern Penang (SPS) by 96 houses, Central Penang (SPT) by 32 houses and South West
Penang (BD) by 29 houses. No house observed in North East Penang (TL) involves in the
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windstorm occurrence. Meanwhile, there are 100 numbers of houses damaged in 2013 and
approximately, house damage may rise up until year end. Previous data of windstorm
occurrence shows increasing trend yearly.This result is also in line with finding by Majid, et.al,
(2012) stated that number of damages are constantly increase year by year with rapid
growth of development.It was recorded that 29 numbers of occurrence observed in 2010,
43 occurrences in 2011 rise by (48.28%) from previous year, 56 occurrences in 2012 by
(30.23%), thus, in 2013 there was 29 occurrences recorded until month of August. Tendency
for wind storm occurrence to hike up for year 2013 most probably is due to the inter-
monsoon season during October to November.
Figure 4: Yearly number of houses damaged with regards to five districts in Penang state
Meanwhile, Figure 5 summarizes recent trend windstorm occurrence which clearly indicates
the tendency of houses damaged increase yearly throughout four years data period. In
year 2013 shows decreasing trend because the data recorded were cut off by August.
House damaged cases mainly affected the low rise buildings. Majority low rise buildings
among the building structures in Malaysia face the great impact during the event. It was
identified that 80% of the cases caused damaged to the roofing systems due to the
thunderstorm in Peninsular Malaysia. Damage breakdown shows that 47% damage in steel
sheet roofing, 30% damage on trusses system, 13% damage on roof tiles and 20% for other
related damages stated by Majid, et. al (2012).Windstorm occurrence in Malaysia must be
considered. Building codes and guidelines in Malaysia need to be revised very carefully.
Figure 5: Windstorm summary in Penang state.
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CONCLUSION
This study shows that windstorm is a phenomenon that should be taken seriously for many
reasons in Malaysia. It is important to note that a rise in severe windstorm events, thus,
increase the damages and losses and also human life. Damages, losses and social problems
are casualties that could create by this natural disaster. All natural disasters including those
related to wind have enormous socio-economic implications in terms of the sustainability of
the human habitat and built environment. Although Malaysia is not in cyclone prone region,
a good awareness should be taken to reduce the loss due to windstorm and loss of life.
REFERENCES
Yusoff A. (2005), “A study on the characteristics of thunderstorm at Telekom Malaysia
communication center, Seberang Jaya, Penang”., MSc Dissertation,School of Civil
Engineering, UniversitiSains Malaysia.
Holmes J. D. (2001). “Wind Loading of Structures”. Spon Press, Taylor & Francis Group, New
York.
Majid, T.A, NoramI.Ramli, Ali M.I., Syamsul, M.H.Saad, Malaysia Country Report 2012: Wind
Related Disaster Risk Reduction and Wind Environmental Issues.
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THE STABILITY OF TEMBURUNG FORMATION IN BEAUFORT AREA, SABAH
Ismail Abd Rahim
Natural Disasters Research Unit, School of Sciences & Technology,
Universiti Malaysia Sabah, Jalan UMS
88400 Kota Kinabalu, Sabah, Malaysia
Phone: 088 320000 (5734/5999)
Fax: 088 435324
ABSTRACT. The aim of this paper is to determine the stability and to propose preliminary rock
cut slope protection and stabilization measures for Oligocene to Late Eocene Temburung
Formation in Beaufort, Sabah. Six (6) slopes were selected for this study. Geological mapping,
discontinuity survey, kinematic analysis and prescriptive measure were used in this study.
Results of this study conclude that the modes of failures are wedge, planar, circular and
complex. Gunite, soil nail, weep hole, slope reprofiling, terrace, drainage and retaining
structure are proposed stabilization and protection measures for the slope in the study area.
KEYWORDS: Temburung formation, Beaufort, mitigation measure, slope stability, mode of
failure
INTRODUCTION
The development of instabilities in rock cut slope is a serious problem with a significant
economic and social impact. Catastrophic failures of rock cut can result in property
damage, injury and even death.
The development of instabilities depends on the combination of the rock mass
characteristics (strength, lithology, structure and degree of weathering), the preservation of
the slope and how water enters into the system, the relationship between the rainfall-runoff
and the groundwater. Combinations of these factors contribute to the large number of
accidents during and after construction work, as well as loss of both material resources and
lives (Uribe-Etxebarria et al., 2005).
In Beaufort area, especially in Temburung formation this situation appear related to rock
mass characteristic and its abundant rainfall. Intense jointing and shearing and thick shale
layers were characterized the rock mass of the Temburung formation to small (1cm3 – 1m3)
polygonal block shape, irregular block type and low strength.
The occurrence of slope failures in km 130.1 and 112 on 9 April 2013 (Photograph1A and 1B)
and km 123.8 of Beaufort-Tenom railway on 2008 (Photograph 1C) with 1 mortality has
becomes an issue for this study.
This study was conducted in Temburung formation only because the slope failures was
happened in Temburung formation. There are six (6) rock cut slopes have been evaluated
and identified as slope 1, 2, 3, 4, 5 and 6. The locations of rock cut slopes for this study are
shown in Figure 1.
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Photograph 1 Slope failures. A - km 130.1 (2013); B – km 112 (2013); C – km 123.8 (2008).
METHODOLOGY
Geological mapping, discontinuity survey and kinematics analysis have been used to
evaluate the stability of slope in study area. Geological mapping includes lithological and
structural identification, measurement and interpretation. For discontinuity survey, scanline
method was conducted by following ISRM (1981) procedure. DIPS 5.0 software package
(Rocscience, 2009) has been used to identify the discontinuity set or average orientations of
discontinuity sets.
Evaluation of rock slope stability was performed by kinematic analyses (Markland, 1972).
Kinematic refers to the motion of rock mass bodies without reference to the forces that
cause them to move (Goodman, 1989). A kinematic analysis is very useful to investigate
possible mode of failure of rock masses which contain discontinuities (Jeongi-gi Um &
Kulatilake, 2001).
In the Kinematic analysis, it is assumed that the friction angle (Ø) for the discontinuity planes is
about 30 (Kliche, 1999; Hoek & Bray, 1981). This value is assumed to represents average
friction angle for the slope material. However, it is noted that this value may be decreased
down to as low as 27 in the presence of seepage along the discontinuity planes, or
increased up to 35 in dry, very hard and rough discontinuity surface.
The slope stabilization and mitigation measures were determined by prescriptive measures
(Yu et al., 2005) and using conventional engineering practices.
GEOLOGY
The study area is underlain by the Crocker and Temburong Formations, which is inter-
fingering between others as well as alluvium deposits with the age of Pleistocene and Recent
(Figure 1). These two formations are part of turbidite deposit.
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Figure 1 General geological map and slope locations of the Beaufort-Tenom railway area
(modified from Wilson & Wong, 1954; Yin, 1985).
The Crocker Formation is Late Eocene to Early Miocene ages and composed of a few types
of Lithology such as thick sandstone unit, interbedded sandstone and shale unit and thick
shale unit. The dominant north-south strike of the Crocker Formation gives rise to a series of
elongated parallel ridges. The major structural pattern in this area is dominated by thrust
faults trending northeast-southeast with minor folds system plunging to northeast (Wilson &
Wong, 1964).
The Temburung formation deposited by the age range from Oligocene to Early Miocene
(Sanudin & Baba, 2007). The Temburong Formation slightly deference from Crocker
Formation by its lithological unit, it composed of interbedded thick shale and/without thin
siltstone unit (Photograph 2A), shale thicker than sandstone interbedded unit (Photograph
2B) and sandstone thicker than shale interbedded unit (Photograph 2C).
The Pleistocene alluvial terrace is composed of coarse gravel in most outcrops. The Recent
alluviums is observed along the riverside and flood-plain area.
Photograph 2 Rock unit. A – thick shale and/without thin siltstone unit; B - shale
thicker than sandstone interbedded; C - sandstone thicker than shale unit.
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RESULTS
The six (6) slopes, rock mass characterization and slope instability in the study area are shown
in Photograph 3 and Table 2. The slopes are showing varied lithological units i.e. thick shale
and/without thin siltstone unit, shale thicker than sandstone interbedded unit and sandstone
thicker than shale unit.
Photograph 3 Slopes. A – slope 1; B – slope 2; C – slope 3; D – slope 4; E – slope 5; F – slope 6.
Table 2 Slope, rock mass characteristic and instability.
Slope Characteristic Instability
Observation
1 Sandstone thicker than shale unit. Highly jointed and faulted. No
seepage. Low discontinuity persistence. Small block size and
irregular block shape.
Rock block, wedge
plane
2 Shale thicker than sandstone unit. Highly jointed and sheared. No
seepage. Low discontinuity persistence. Small block size and
irregular block shape.
Rock block, wedge
plane, debris
deposit
3 Sandstone thicker than shale unit. Highly jointed and faulted.
Seasonal seepage. Low discontinuity persistence. Small block size
and irregular block shape.
Rock block, wedge
plane, debris
deposit
4 Thick shale and thin siltstone unit. Highly jointed, sheared and
faulted and sheared. Water seepage occurs. Low discontinuity
persistence. Very small block size and irregular block shape. Soil
like.
Circular plane,
debris deposit
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5 Shale thicker than sandstone unit. Highly jointed and faulted.
Seasonal seepage. Low discontinuity persistence. Very small block
size and irregular block shape.
Wedge plane,
debris deposit
6 Sandstone thicker than shale unit. Highly jointed, sheared and
faulted. Seepage occurs. Low discontinuity persistence. Small block
size and irregular block shape.
Circular plane,
debris deposit
(colluvium deposit)
The rock mass is generally highly jointed, sheared and faulted. Seepage occurs in the slope
represented by moderate to thick shale beds. The persistence of discontinuity is low unless
the bedding planes. The block size is small for sandstone beds but very small for thin
sandstone and thick shale beds. The block shape is tabular to irregular. The highly weathered
thick shale unit shows the rock mass as soil like and weak.
Observed instability features on the slope face are failure planes [circular (Photograph 4A),
wedge (Photograph 4B), and complex failures (Photograph 4C)], debris deposits and rock
blocks. Results of the Markland test are shown in Figure 2 and Table 3. The potential modes of
failures from the test are wedge, circular, planar and complex failures.
Photograph 4 Slope failure. A – circular failure; B – wedge failure; C – complex failure.
Figure 2 Markland test for slope 1 to slope 6.
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Table 3 Slope, rock mass characteristic and instability.
Slope Characteristic Instability
Observation
1 Sandstone thicker than shale unit. Highly jointed and faulted. No
seepage. Low discontinuity persistence. Small block size and
irregular block shape.
Rock block, wedge
plane
2 Shale thicker than sandstone unit. Highly jointed and sheared. No
seepage. Low discontinuity persistence. Small block size and
irregular block shape.
Rock block, wedge
plane, debris
deposit
3 Sandstone thicker than shale unit. Highly jointed and faulted.
Seasonal seepage. Low discontinuity persistence. Small block size
and irregular block shape.
Rock block, wedge
plane, debris
deposit
4 Thick shale and thin siltstone unit. Highly jointed, sheared and
faulted and sheared. Water seepage occurs. Low discontinuity
persistence. Very small block size and irregular block shape. Soil
like.
Circular plane,
debris deposit
5 Shale thicker than sandstone unit. Highly jointed and faulted.
Seasonal seepage. Low discontinuity persistence. Very small block
size and irregular block shape.
Wedge plane,
debris deposit
6 Sandstone thicker than shale unit. Highly jointed, sheared and
faulted. Seepage occurs. Low discontinuity persistence. Small block
size and irregular block shape.
Circular plane,
debris deposit
(colluvium deposit)
DISCUSSION
Six (6) rock cut slopes of the Temburung Formation were analyzed by kinematic analysis
along Beaufort-Tenom railway. The Temburung Formation has varies engineering geological
properties and two to four discontinuities sets including bedding planes or joints.
According to the Markland’s test, a plane failure is likely to occur when a discontinuity dips in
the same direction (within 20o) as the slope face, at an angle gentler than the slope angle
but greater than the friction angle along the failure plane. A wedge failure may occur when
the line of intersection of two discontinuities, forming the wedge-shaped block, plunges in
the same direction as the slope face and the plunge angle is less than the slope angle but
greater than the friction angle along the planes of failure. A toppling failure may result when
a steeply dipping discontinuity is parallel to the slope face (within 10o) and dips into it (Hoek
& Bray, 1981; Ismail Abd Rahim, 2011).
Combination of more than two wedge failures with other failure such as planar, toppling or
circular will forming complex failure. Intersection of J4 with J2, J1 with B and J1 with J2 in slope
1, 5 and 6 contributes to the formation of wedge failures, respectively. Intersection of J4 with
J1, J4 with J2 and J1 and J2 in slope 2 but more than 20o difference of intersection lines with
dip direction of slope faces has forming partly potential wedge failure. Combination of
planar and wedge failures in slope 5 contribute to the formation of complex failure as
occurred in 2008. Possibilities of wedge, planar and circular failures in slope 3 have made
these slopes partly potential for complex failure.
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Application of geological characteristics, properties of the rock mass and mode of failures to
proposed remedial measures for rock cut slopes was used widely (Amin, 1999; Kentil & Topal,
2004; Ismail Abd Rahim et al., 2010). Summary of the slope protection and stabilization
measures for the study area are shown in Table 4.
Slope reprofiling is recommended for slope 3. All slope needs to be install with subsurface
drainage but guniting. Slopes 6 needs to be provided by surface drainage system and
soilnail for slope 2, 3, 4, 5 and 6. Terrace must be made in slope 6 and retaining structures
need to be built in slope 5 and 6.
Table 4 Slope protection and stabilization measures.
Slope Slope
reprofiling Gunite
Subsurface
drainage Drainage
Soil
nail Terrace
Retaining
structure
1 / /
2 / / /
3 / / / /
4 / / /
5 / / / /
6 / / / / / /
CONCLUSION
Conclusions of this study are;
1. The potential modes are wedge, planar, circular and complex failures.
2. Most of the rock cut slopes are unstable unless slope 1.
3. Slope refrofiling, guniting, subsurface drainage, drainage, soil nailing, terrace and retaining
structure are proposed mitigation and stabilization measures.
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Amin, A. A. 1999. Geologic hazard along part of Al-sayl-Alkabeir Al-Jammun road in Saudi
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Hoek, E. & Bray, J. W. 1981. Rock Slope Engineering. 3rd ed. Institution of Mining and
Metallurgy, London, 359pp.
Ismail Abd Rahim, Sanudin Tahir, Baba Musta, & Shariff A. K. Omang. 2010. Slope Stability
Evaluation of Selected Rock Cut Slope of Crocker Formation in Kota Kinabalu, Sabah.
Proceeding of the 3rd Southeast Asian Natural Resources and Environmental
Management (SANREM 2010), 3-5 August 2010, Promenade Hotel, Kota Kinabalu,
Sabah.
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Ismail Abd Rahim. 2011. Rock mass classification system of the Crocker Formation in Kota
Kinabalu for rock slope engineering purposes, Sabah. PhD Thesis. Universiti Malaysia
Sabah, Kota Kinabalu.
Ismail Abd. Rahim, Sanudin Haji Tahir, Baba Musta, & Rodeano Roslee. 2006. Slope Stability
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Slope of the Three Gorges Dam Site in China. Geotechnical and Geological
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Rigid Wedge Slide Type of Failure is Expected. Imperial College Rock Mechanics
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Uribe-Etxebarria G, Morales T, Uriarte JA, Ibarra V. 2005. Rock Cut Stability Assessment in
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Wilson, R.A.M. and Wong, N.P.Y., 1960. The geology and mineral resources of the Labuan and
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