Hazard Risk Mitigation in Europe and Central Asia

WORLD BANK Workshop Istanbul, October 26-28, 2004

Seismic risk mitigation in the Seismic risk mitigation in the

Vrancea region, RomaniaVrancea region, Romania

Dan Lungu

Technical University of Civil Engineering, Bucharest and

National Institute for Building Research, Bucharest

Original Presentation has been modified for Internet Use.

Contents

1. The Romanian earthquake hazard and the 1977 disaster

in Bucharest

2. Vulnerability (fragility) of existing building stock and Codes for

earthquake resistance of buildings

3. National programs and international projects for seismic risk

mitigation in Romania

"Nowhere else in the world is a center of population so exposed to earthquakes originating repeatedly from the same source"

Charles Richter. 15 March 1977, Letter to the Romanian government

World Map of Natural Hazards prepared by the Münich Re, 1998 indicates for Bucharest: “Large city with Mexico-city effect”

1. The Romanian earthquake hazard and the 1977

disaster in Bucharest

“The unusual nature of the ground motion and the extent and distribution of the structural damage have important bearing on earthquake engineering efforts in the United States.”

Jennings & Blume, NRC & EERI Report

1000 yr catalogue of Vrancea earthquakes

• Major historical events and major 20 century earthquakes

• Number of events/century, having intensity larger than 9 and 7

Catalogue time span, years

Obs Epicentral intensity

(MSK) 984 - 1900 1901 - 2000

I0 9.0 1 2

I0 7.0 10 16

20 century shows the highest seismic activity of the Vrancea

source

≥

≥

Event

Epicentral intensity Io

Focus depth.

km

Moment

magnitude Mw

Obs

1802, October 26 1829, November 20 1838, June 23

> 9 8 8

7.9 Largest Vrancea event ever occurred

1940, November 10 1977, March 4 1986, August 30

9 8/9 7/8

150 109 133

7.7 7.5 7.2

Largest seismic losses ever experienced

≥≥

• Destroyed or seriously damaged 33,000 housing units and

caused lesser damage to 182,000 other dwellings

•Destroyed 11 hospitals and damaged 448 others hospitals, etc.

March 4, 1977 earthquake

Mw = 7.7 ; h = 109 km

Killed 1,578 people (1424 in Bucharest)

Injured 11,221 people (7598 in Bucharest)

The World Bank estimation of losses (Report 16.P-2240-RO, 1978):

• Total losses in Romania : 2.05 billion USD (100%)

Construction losses : 1.42 (70%)

Building and housing losses : 1.02 (50%)

PSHA, Probabilistic seismic hazard assessmentLungu, Demetriu, 1994-2004

1. Recurrence of Vrancea magnitude

D a t e

M o m e n t

m a g n i t u d e , M w

M e a n r e c u r r e n c e i n t e r v a l 1

)w,o

Mw,max

.687(M1e1

)w

Mw,max

1.687(Me1w

1.687M8.654e1Mw) (

2 6 O c t 1 8 0 2

8 . 0 7 . 9

1 0 N o v 1 9 4 0

7 . 7 7 . 6

4 M a r c h 1 9 7 7

3 0 A u g 1 9 8 6

7 . 5 7 . 3 7 . 2

8 2 5 0 4 0

5 0 y r

1 4 8 1 0 8

1 0 0 y r

7 7 8 y r 3 5 6

4 7 5 y r

2. Attenuation of Vrancea strong ground motion

0.5020.006h0.0005R1.000lnR1.053M3.098lnPGAw

PGA - peak ground acceleration at the site

Mw- moment magnitude: Mw,0 = 6.3 Lower threshold magnitude; Mw, max= 8.1 Max credible

R - hypocentral distance to the site; h - focal depth;

ln PGA= 0.502- standard deviation of lnPGA

Database: 80 triaxial records at 48 free-field stations in Romania, R. of Moldavia, Bulgaria

MSK intensity,from seismic zonation map

Period of construction of building

before 1940

1941-1963 1964-1977 1978-1990 after 1990

VI         

VII          

VIII, Bucharest          

IX         

Pre-code Low-

code Moderate-highcode

Quality of seismic design incorporated into existing buildings stock is modeled by four categories :

Pre-code; Low-code; Moderate-code; High-code.

2. Vulnerability (fragility) of existing building stock

and Codes for earthquake resistance of buildings

3 International lessons unlearnt from the 1977 earthquake

1

“A systematic evaluation should be made of all buildings in Bucharest erected prior to the adoption of earthquake design requirements and a hazard abatement plan should be developed.”

From:

“Observation on the behaviour of buildings in the Romanian earthquake of March 4, 1977” by G. Fattal, E. Simiu and Ch. Cluver. Edited as the NBS Special Publication 490, US Dept of Commerce, National Bureau of Standards, Sept 1977.

2“Tentative provisions for consolidation solutions would preferably be developed

urgently”. From:

“The Romanian earthquake. Survey report by Survey group of experts and specialists dispatched by the Government of Japan (K. Nakano). Edited by JICA, Japan International Cooperation Agency, June 1977.

3

“Bucharest had been microzoned as part of UNESCO Balkan Project, with microzones denoting three levels of risk. The worst destruction occurred in lowest-risk microzone.”

From:

“”Earthquake in Romania March 4,1977. An Engineering Report” by G. Berg, B. Bolt, M. Sozen, Ch. Rojahn. Edited by National Academy Press, Washington, D.C. 1980

The 1977 National strategy for strengthening

damaged buildings

“The retrofitting of buildings must provide: (i) For the old buildings – the same resistance the have before 1940 earthquake (when they survived!);(ii) For the new buildings – the same resistance the have when they were designed”

Letter to the Municipality of Bucharest of the General Inspector for Construction of Romania, based on March 30, 1977, Order of Romanian Government

“Retrofitting of the buildings damaged by the 1977 earthquake will consist of strict local repairing of damaged elements. Additional measures for seismic protection are not allowed.”

Letter to the technical University of Civil Engineering, Bucharest from General Inspector for Construction of Romania and General

Director of Central Institute for Research Design and Coordinator for Construction, July 11, 1977

Importance and exposure class Vulnerability class I II III IV

i 1 1 2 3 ii 1 2 3 3 iii 3

Seismic risk class Matrix

“Seismic risk class 1 buildings”

Building to be immediately retrofitted!

City

Number of vulnerable

buildings

Number of inhabitants

Bacau 6 208.643

Barlad 6 78.786

Braila 4 232.409

Brasov 8 312.481

Bucharest 123+ ... 2.011.305

Buzau 1 146.926

Campina 2 40.297

Iasi 49 347.606

Roman 1 81.731

Suceava 1 118.183

Targu-Mures 1 164.132

Vaslui 6 78.735

Vulnerable residential buildings-from Ministry of Transports, Constructions and Tourism of Romania-

Number of vulnerable schools

City Requiring technical

assessment

Having a technical

report

Having technical

documents

Total

Bacau 1 - - 1 Barlad 11 - - 11 Brasov 7 2 - 9 Bucharest 13 7 2 22 Constanta - - 1 1 Craiova 2 - 5 7 Galati 1 2 - 3 Giurgiu 2 - - 2 Iasi 3 5 - 8 Pitesti - 1 1 2 Ploiesti 1 5 - 6 Sibiu 3 1 - 4 Vaslui 10 - - 10 Total 54 23 9 86

Vulnerable school buildings -from Ministry of Education and Research of Romania-

Vulnerable hospital buildings -from Ministry of Health and Family of Romania-

Number of vulnerable hospitals

CITY Severely damaged.

Requiring immediate technical assessment

Having a technical report

Approved project for retrofitting

Retrofitting in work

Total

Bacau 3 3 Barlad 2 2 Bucharest 13 16 6 10 45 Buzau 9 9 Constanta 7 7 Craiova 4 4 Focsani 2 2 Galati 6 2 1 9 Giurgiu 1 1 Iasi 21 17 2 5 45 Pitesti 2 7 9 Ploiesti 2 2 Sibiu 1 1 Targu-Mures 2 2 Vaslui 4 1 5 Total 68 47 12 19 146

Objectives:

1. Strengthening of “seismic risk class 1” buildings: Legislation + Construction

work;

2. Upgrading of the code for seismic design of buildings and

structures;

3. Seismic instrumentation

3. National programs and International projects for

seismic risk mitigation in Romania

Strengthening work for the 123 highly

vulnerable buildings in Bucharest

October 2004:

3 buildings are fully retrofitted

8 buildings are under retrofitting

16 buildings have retrofitting projects ready

8 buildings are on the waiting list for retrofitting

Upgrading the code for seismic design of buildings and structures

The draft of the New code for earthquake resistance of new structures,

P100-2004, following EUROCODE 8 format, was just issued (Jan 2004)

The draft of the New code for earthquake resistance of existing buildings

and structures: to be prepared !

Name of network Bucharest Romania

(including Bucharest) INCERC & ISC, State Inspectorate for Construction

7 ETNA 31 ETNA New digital networks, installed in 2003

CNRRS & JICA, Japan International Cooperation Agency Project1

11 K2 16 instruments: -11 K2; - 5 ETNA

INCERC

21 instruments: -10 SMA-1 (analog) -9 ADS (digital) -2 digital stations for continuous monitoring

70 instruments: -58 SMA-1(analog) -9 ADS (digital) 3 digital station for continuous monitoring Existing seismic

networks, in 2002 INFP/SFB 461 German Science Foundation Project at University of Karlsruhe

15 K2 41 K2

TOTAL 54 digital instruments 158 instrumentsinstruments

100 digital

Seismic instrumentation in Romania, 2004

JICA technical cooperation project :

“Reduction of seismic risk for buildings and structures in Romania”

• Project signed in 2002, when 100 years of diplomatic relations between

Japan and Romania were celebrated

• Project duration: 5 yr

JICA Project in Romania is based on partnership of 3 institutions:

NCSRR, National Center for Seismic Risk Reduction

UTCB, Technical University of Civil Engineering Bucharest

INCERC, National Institute for Building Research, Bucharest

under the authority of:

MTCT, Ministry of Transports, Constructions and Tourism.

Total cost of the project

5.27 mill. USD

• Equipment cost 2.7 mill. USD:

- Soil testing laboratory

- Structure testing laboratory

- Seismic instrumentation network in Bucharest and Romania

(free field, borehole, buildings)

• 16 Romanian young students/engineer to be trained in Japan

• 34 Japanese short term and long term experts in Romania

Equipments for soil testing

and investigation

Triaxial testing equipment

Drilling equipment

SPT/CPT testing equipment

Equipment delivered by JICA and installed together with two OYO technicians

and one Japanese expert:

- Altus K2 accelerometer (11)

- borehole sensors FBA-23DH (14+1)

- sensors EPISENSOR ES-T (9+1)

- ETNA accelerometer (5+1)

Seismic network

Free fieldoutside Bucharest

ETNA6 sites

BoreholeBucharest

K27 sites

3 sensors(surface +

2 in borehole)

BuildingBucharest

K24 sites

Equipment for strong ground motion observation

Borehole sensor

Altus K2 accelerometer

Borehole sensor

Free field

Shallow borehole 24÷30m

Deep borehole

60÷153m

Surface and borehole cables

Borehole seismic instrumentation

Bucharest - Location of borehole instrumented sites

Instrumented buildings in Bucharest

RISK U.E. Project

An advanced approach to earthquake risk scenarios with applications to

different European towns

Flow charts of RISK UE Project (P. Mouroux)

Workpackage 1 of RISK-UE

European distinctive features, inventory database and typology

Objective 1 - Distinctive features of European towns

• Town identity

• Population characteristics

• Urbanised area and elements at risk

• Impact of past earthquakes on elements at risk

• Strong motion data in the city and seismic hazard

• Geological, geophysical and geotechnical information

• Evolution of earthquake resistant design codes• Earthquake risk management efforts

References

Classification of buildings occupancy

1) Buildings with capacity greater than 150 people2) Buildings with capacity greater than 300 people or where more than 300 people congregate in one area

Objective 2 - Europe inventory database and typology

Building typology matrix, BTMLabel Building type description Height description Code level*

Name No. ofstories

Height h,m

N L M H

RC Reinforced concrete structures

RC1 Concrete moment frames Low-riseMid-riseHigh-rise

1 - 34 - 78+

h 99 < h 21

h > 21RC2 Concrete shear walls Low-rise

Mid-riseHigh-rise

1 - 34 - 78+

h 99 < h 21

h > 21RC3

3.1

3.2

Concrete frames with unreinforced masonryinfill walls

Regularly infilled frames

Irregularly frames (i.e., irregular structuralsystem, irregular infills, soft/weak story)

Low-riseMid-riseHigh-rise

Low-riseMid-riseHigh-rise

1 - 34 - 78+

1 - 34 - 78+

h 99 < h 21

h > 21

h 99 < h 21

h > 21

RC4 RC Dual systems (RC frames and walls) Low-riseMid-riseHigh-rise

1 - 34 - 78+

h 99 < h 21

h > 21RC5 Precast Concrete Tilt-Up Walls Low-rise

Mid-riseHigh-rise

1 - 34 - 78+

h 99 < h 21

h > 21RC6 Precast Concrete Frames with Concrete

shear wallsLow-riseMid-riseHigh-rise

1 - 34 - 78+

h 99 < h 21

h > 21

*Code level N - no code; L - low-code (designed with unique arbitrary base shear seismic coefficient); M - moderate-code; H - high-code (code comparable with Eurocode 8)

Town Inhabitants Population density,persons/km2

Population growth,20th century*

GDP/person(approx.)

EuroBarcelona 1,503,451 15,176 1970 22,000Bitola 79,456 12,600 1990 1,620Bucharest 2,011,305 10,806 1989 1,980Catania 333,075 6,125 1971-1991 9,000-15,000Nice 342,738 4,766 1980 20,000Sofia 1,133,183 4,680 1985 1,630Thessaloniki 1,048,151 21,600 1991 15,290

Population and yearly GDP

I. Population and Building exposure

Comparative study for 7 towns

0

500,000

1,000,000

1,500,000

2,000,000

2,500,000

Barcelona Bitola Bucharest Catania Nice Sofia Thessaloniki

WP1. UTCB

Population

Population of the 7 towns

Barcelona Bitola Bucharest Catania Nice Sofia Thessaloniki

0

5,000

10,000

15,000

20,000

25,000

WP1. UTCB

Population density, persons/km2

Population density in the 7 towns

Barcelona Bitola Bucharest Catania Nice Sofia Thessaloniki0

20,000

40,000

60,000

80,000

100,000

120,000

NA NA

WP1. UTCB

Number of

buildings

Number of buildings for the 7 towns

0

100,000

200,000

300,000

400,000

500,000

600,000

700,000

800,000

900,000

Barcelona Bitola Bucharest Catania Nice Sofia Thessaloniki

WP1. UTCB

Number of

housing units

Number of housing units for 7 towns

Barcelona Bitola Bucharest Catania Nice Sofia Thessaloniki3.5

4.5

5.5

6.5

7.5

8.5

9.5

10.5

NA

WP1. UTCB

LARGEST HISTORICALEVENT

3.5

4.5

5.5

6.5

7.5

8.5

9.5

10.5

WP1. UTCB

Barcelona Bitola Bucharest Catania Nice Sofia Thessaloniki

20th CENTURY

MSK local-intensity of largest experienced earthquake for the 7 towns

II. Earthquake hazard and earthquake instrumentation

Building stock age in the 7 towns versus

Seismic codes inter-benchmark periods

III. Vulnerability and typology of European buildings stock

Masonry buildings types for the 7 towns

Buildings typology

World Bank project in Romania

Component B:

Earthquake Risk Reduction ~35%

Subcomponents:

•Strengthening of high priority buildings and lifelines

•Design & supervision

•Building code review and study of code enforcement

•Professional training in cost effective retrofitting

Component A:

Strengthening of Disaster management capacity ~5%

Components C D& E: Flood, Pollution & Project Management 60%

Implementation unit for Component B at

MTCT, Ministry of Transports, Construction and Tourism

Romanian Government has been approved the following list of

buildings to be retrofitted on April 7, 2004

Type of buildings In

Bucharest In seismic counties

of Romania Total

Emergency bldg 12 18 30 Hospitals bldg 13 9 22 Educational bldg 6 6 12 Important public bldg 6 - 6 Essential facilities - 14 14

Total 37 47 84

The buildings list is splitted in two lists: priority list and additional list.

Priority list of buildings contains 65 buildings i.e:

Type of buildings In

Bucharest In seismic counties

of Romania Total

Emergency bldg 11 187 28 Hospitals bldg 12 7 19 Educational bldg 6 6 12 Important public bldg 6 - 6

Total 35 30 65

E m e r g e n c y fa c i l i t ie s

3 0 %

P u b l ic1 2 %

E d u c a t io n a l1 8 %

H o s p ita ls4 0 %

B u c h a r e s t

C o m m u n ic a t io n2 6 % E m e r g e n c y

fa c i l i t ie s3 9 %

P u b lic4 % E d u c a t io n a l

1 1 %H o s p ita ls

2 0 %

O th e r c i t ie s

Distribution of buildings with occupancy

O t h e r c i t ie s6 2 %

B u c h a r e s t3 8 %

O t h e r c i t ie s3 3 %

B u c h a r e s t6 7 %

Distribution of number of buildings to be retrofitted

Distribution of cost for buildings to be retrofitted

  

0

1 0

2 0

3 0

4 0

5 0

6 0

N u m b e r o f s t o r i e s

Nu

mb

er o

f b

uild

ing

s

5 8

B u c h a r e s t

0

1 0

2 0

3 0

4 0

5 0

6 0

N u m b e r o f s t o r i e s

Nu

mb

er o

f b

uild

ing

s

5 8

O t h e rc i t i e s

Distribution of buildings with number of stories

Distribution of buildings with floor area

0

5

1 0

1 5

T o t a l f l o o r a r e a , m ²

Num

ber o

f bui

ldin

gs

2 5 0 5 0 0 1 0 0 0 1 5 0 0 2 0 0 0 3 0 0 02 5 0 0

B u c h a r e s t

0

5

1 0

1 5

T o t a l f l o o r a r e a , m ²

Num

ber o

f bui

ldin

gs

2 5 0 5 0 0 1 0 0 0 1 5 0 0 2 0 0 0 3 0 0 02 5 0 0

O t h e rc i t i e s

0

2

4

6

8

1 0

1 2

1 4

1 6

1 8

Num

ber o

f bui

ldin

gs

Y e a r o f c o n s t r . 1 9 0 0 1 9 4 0 1 9 6 3 1 9 7 8 1 9 9 2

P 1 3 - 6 3 P 1 0 0 - 7 8

. . .

P 1 0 0 - 9 2B u i l d i n g c o d e N o c o d e

5 9 %

4 1 %

0

2

4

6

8

1 0

1 2

1 4

1 6

1 8

Num

ber o

f bui

ldin

gsY e a r o f c o n s t r . 1 9 0 0 1 9 4 0 1 9 6 3 1 9 7 8 1 9 9 2

P 1 3 - 6 3 P 1 0 0 - 7 8

. . .

P 1 0 0 - 9 2B u i l d i n g c o d e N o c o d e

4 0 %

5 6 %

4 %

Distribution of buildings with year of construction

Distribution of buildings with present seismic intensity map

1

77

9

0

10

20

30

40

50

60

70

80

90

7 8 9

Seismic intensity

Num

ber o

f bui

ldin

gs

VII VIII IX MSK

World Bank report

“Preventable Losses: Saving Lives and Property through Hazard

Risk Management”

Strategic Framework for reducing the Social and Economic Impact of

Earthquake, Flood and Landslide Hazards in the Europe and Central Asia

Region

Draft, May 2004

• Romania is regarded as one the most seismically active countries in

Europe

• Bucharest is one of the 10 most vulnerable cities in the world.

Recommendations for Romania:

• Upgrade the legal framework for hazard specific management;

• Review the existing buildings code for the retrofitting of vulnerable

buildings;

• Conduct a comprehensive public awareness campaign for the

earthquake risk;

• Invest in hazard mitigation activities in order to reduce the risks

caused by earthquakes;

• Develop financing strategy for catastrophic events.