experimental study on stren gth … · consolidation settlement of fiber reinforced compacted clay....

http://www.iaeme.com/IJCIET/index.asp 2027 [email protected]

International Journal of Civil Engineering and Technology (IJCIET) Volume 8, Issue 4, April 2017, pp. 2027–2035, Article ID: IJCIET_08_04_231 Available online at http://www.iaeme.com/IJCIET/issues.asp?JType=IJCIET&VType=8&IType=4 ISSN Print: 0976-6308 and ISSN Online: 0976-6316 © IAEME Publication Scopus Indexed

EXPERIMENTAL STUDY ON STRENGTH CHARACTERISTICS OF PALM FIBER

REINFORCED SOIL STABILIZE USING BAGASSE ASH

Ankita Sonkar M Tech, Geotechnical Engineering, SRM University, Chennai, Tamil Nadu, India

S. Srividhya Assistant Professor (O.G), SRM University, Chennai, Tamil Nadu, India

ABSTRACT Expansive soils which are also known as problematic soils are having swelling

and shrinkage properties which result in damage to the structure constructed over it. This paper investigated the resultant strength and swelling behavior when randomly distributed palm fibers are used to reinforce expansive soil and stabilized using bagasse ash. The soil was examined for compaction test and unconfined compression test at four different fiber contents (0.25%, 0.5%, 1% and 1.25%). The effect of aspect ratio and different percentage of fiber on the behavior of the composite soil specimen with curing were studied. The Maximum Dry Density (MDD) of fiber stabilized soils goes on decreasing and Optimum Moisture Content (OMC) goes on increasing with increase in the percentage of fiber in soil. The result indicated that inclusion of palm fiber increases the ductility and strength of soil. In order to further increase the strength of palm fiber reinforced soil varying percentage (1%, 2%, 3%, 4%) of bagasse ash is added. An optimum fiber content of 0.5% (by weight) showed the maximum result in the strength values whereas the combination of palm fiber and bagasse ash showed a decrease in strength value. Key words: MDD, OMC, UCC Value, palm fiber, bagasse ash.

Cite this Article: Ankita Sonkar and S. Srividhya, Experimental Study on Strength Characteristics of Palm Fiber Reinforced Soil Stabilize Using Bagasse Ash. International Journal of Civil Engineering and Technology, 8(4), 2017, pp. 2027–2035. http://www.iaeme.com/IJCIET/issues.asp?JType=IJCIET&VType=8&IType=4

1. INTRODUCTION The design and construction of infrastructure project on expansive soil is a challenging task for geotechnical engineers. Expansive soil shows major volume change due to change in the moisture content of soil. The mineral containing in expansive soils are Montmorillonite clay

Ankita Sonkar and S. Srividhya


which is having the capability of absorbing water, such soils tend to swell and shrink by absorbing water causing severe suffering to the structures. Therefore, such soil needs to be treated before commencing the construction to reduce the structural damage and to increase the strength of the soils.

In India, expansive soil deposit is known by the name “black cotton soil” which are predominate in the states of Gujrat, Maharashtra, Madhya Pradesh, Andhra Pradesh, Karnataka and Tamil Nadu. Expansive soils having high plasticity and compressibility, small shear strength when saturated and show very high volume change during drying and wetting. With growing, environmental concern application of natural fiber attracts scientist and researcher to its own substantial advantage. Palm fibers have been used to make a raincoat, ropes because of the brilliant stiffness and antibacterial properties of these fibers. Palm fibers exhibit good structural aspects as well as tensile and chemical properties. Nowadays reinforcing the soil with different fibers increased attention for geotechnical engineers.

Palm fiber with physical properties such as tensile strength, light weight and cheap rate will make it more efficient to use as soil reinforcement. Due to variation in water content, palm fiber may experience volume change which has an effect on the bond between the fibers and soil. Hence palm fiber which is low in cost can be considered as best option for reinforcing the soil. It can be used to increase the slope stability of highway embankment, to increase the subgrade of road or highway and to improve landfill liner and covers.

India is the second largest sugar producing country in the world. Bagasse is the matted cellulose fiber residue which is generated after the juice has been extracted from sugarcane plant.

In this paper, an attempt was made to study the effect of palm fiber and bagasse ash in expansive soil.

2. LITERATURE REVIEW Many types of research have been carried out on natural fiber and bagasse ash for the stabilization of expansive soil. A.R.Estabragh et al (2012) [1] studied on the strength behavior of clay when it is combined with natural fiber. This study showed the result of discrete palm fiber on the randomly reinforced clay soil. Tests which carried out were consolidation and triaxial test. The total stress and effective stress increases with fiber content. Koonnamas Punthutaecha et al (2006) [6] made his study on the swelling and shrinkage behavior of expansive soil stabilized with both fiber and recycled fiber ash. Combined treatment with fly ash and nylon fiber provided the maximum improvements to control soil properties. S.M.Marandi et al (2008) [14] experimented on the silty sand soil from earthquake city of Bam situated in the southeast of Iran which is composite with palm fiber. UCC and CBR tests were conducted to check the strength and ductility of palm fiber reinforced soil. Rabindra Kumar Kar (2008) [12] investigated on the fiber reinforced cohesive soil. The test which was included is consolidation test. The investigation has made on the on the impact of consolidation settlement of fiber reinforced compacted clay. Test on the fiber reinforced clay concluded that with the increase in fiber length and fiber inclusion the coefficieht of consolidation increases. Manjunath K.R. et al (2013) [7] determined the strength behavior of black cotton soil which is reinforced with sisal fiber and lime. The combination of lime and sisal fiber increases compressive strength up to 0.75%. K.S.Gandhi (2014) [6] made an experimental study on expansive soil at surat region modified using bagasse ash and wood ash. Swell potential of expansive decreases because bagasse ash dries wet soil and cementing the soil particles. Soundara et al (2015) [16] made his observation on the effect of fiber on properties of clay. Omid Azadegan et al (2012) [10] made laboratory study on the palm fiber reinforced clay to get the bulging, cracking and strength behavior. Tonghua zhang et al

Experimental Study on Strength Characteristics of Palm Fiber Reinforced Soil Stabilize Using Bagasse Ash


(2015) [17] investigated the structure and properties of palm leaf sheath fiber. From the above literature, it is concluded that fiber is inert plastic material which gives good tensile strength to the natural soil which could be used to stabilize the soil and boost up the strength of soil. The inclusion of fiber in the soil result in the soil to be more soft and ductile this elastic behavior motivated the reinforced soil to fail at the higher axial strain. Bagasse ash increase strength of soil specimen by dries the wet soil which will be suitable for construction on the expansive soil as compared to wood ash. The objective of this study is to determine Optimum Moisture Content (OMC) and Maximum Dry Density (MDD) of untreated and palm fiber reinforced (0.25%, 0.5%, 1% &1.25%) soil by conducting proctor compaction test for a soil sample. To estimate the optimum content of palm fiber (0.25%, 0.5%, 1% &1.25%) required for reinforcing untreated soil by conducting unconfined compressive strength (UCC). To evaluate the strength characteristics of optimized palm fiber reinforced soil stabilizing with bagasse ash (1%, 2%, 3%, and 4%) by conducting UCC.

3. MATERIAL AND PROPERTIES

3.1. Soil The soil is collected from Chennai city of Tamil Nadu state of India at a depth of 2m below the ground level. Dried soil was sieved through 425μ IS sieve before conducting the experiment. Soil which is used in this study is highly compressible clay. It is expansive in nature which will create distress to the structure hence it needs to be stabilized. The basic properties of soil are concluded in Table 1. The value of the free swell index (FSI) is 70% which shows that the soil is highly expansive. From the plasticity index chart, it is found that soil is highly compressible clay. The unconfined compression strength value (UCC) for virgin soil is 166 kPa which needs to be stabilized to overcome the distress in the building.

Table 1 Index properties of soil

Description Result Free swell index 70% Specific gravity 2.6 Plastic limit 32.6% Liquid limit 67% Shrinkage limit 7%

Type of soil Highly compressible clay (CH)

Standard Proctor test

MDD 1.6 g/cc OMC 17%

UCC 166 kPa

3.2. Palm Fiber Palm fibers which are obtained from the palm tree were locally available in the market. These palm fiber will be cut to pieces of 2 cm length and is randomly mixed with soil in varying percentages (0.5%, 0.25%, 1%, and 1.25%). The properties of palm fiber are mentioned in Table 2.



Table 2 Physical properties of palm fiber

Physical properties Values Length of fiber 2 cm Water absorption in 24 hrs 0.6% Tensile strength 8.57MPa Aspect ratio 6.6

3.3. Bagasse Ash Bagasse is locally available in the sugarcane market which is incinerated to form bagasse ash. Bagasse ash is having the potential to replace the water from the expansive soil. Chemical properties of bagasse ash were found out by Scanning Electron Microscope or SEM analysis which shows that it is rich in calcium content. From SEM analysis it is observed that it contain less amount of silica content. Basic properties of bagasse ash are shown in table 3.

Table 3 Properties of Bagasse ash

4. RESULT AND DISCUSSION

4.1. Standard Proctor Test Standard proctor test was carried out on the soils containing palm fiber of different percentages such as 0.25%, 0.5%, 1% and 1.25%.This test is carried out to determine the maximum dry density (MDD) and optimum of moisture content (OMC).

Figure 1 Standard proctor test graph for different Percentage of palm fiber

PROPERTIES VALUES Specific gravity 1.8 Specific surface area (m2/kg) 900 Fineness passing(%) 95 CaCO3 74.33% by weight

SiO2 23.51% by weight



Table 4 MDD and OMC values with different percentage of addition of palm fiber in soil sample A

From Table 4 and from figure 1 it is observed that MDD value goes on decreasing as increasing the palm fiber whereas OMC value constantly increases by increasing the percentage of palm fiber. This variation in OMC is due to the water absorption property of palm fiber. The OMC value for optimum of palm fiber is 18% and MDD is 1.55 g/cm3

4.2. Unconfined Compression Strength Test The stress-strain curve of different percentage of palm fiber with different curing periods which is 3,7,14 and 28 days are shown in figure 1, figure 2, figure 3 and figure 4. Different percentage of palm fiber containing in the soil are 0.25%, 0.5%, 1% and 1.25% and fiber length which we used in this study are 2cm. By addition of palm fiber in the soil it will make the soil flexible. It was also observed that the length of palm fiber affects the strength of soil because by testing the reinforced sample of decreased palm fiber length both maximum and residual strength decreased. The result of the inclusion of palm fiber shows that the strength decreases with increasing the percentage of palm fiber. Figure 5, figure 6 and figure 7 shows the stress-strain with optimum of palm fiber and varying percentage (1%, 2%, 3% and 4%) of bagasse ash. It was observed that the strength increases by increases the bagasse ash which is having pozzolanic properties.

Figure 2 Stress strain curve with addition of palm fiber for 3 days curing

050

100150200250300350400

0 0.02 0.04 0.06 0.08

stre

ss k

Pa

strain ε

0.25%P.F

0.5%P.F

1%P.F

1.25%P.F

S-A + Varying percentage P.F OMC MDD

0.25% P.F. + S-A 17% 1.57 g/cm3

0.5% P.F + S-A 18% 1.56 g/cm3

1% P.F + S-A 20% 1.55 g/cm3

1.25% P.F. + S-A 20% 1.53 g/cm3



Figure 3 Stress-strain curve with addition of palm fiber for 7 days curing



According to above results fibers which replaced the soil, grain controls the behavior of soil specimen under load. The failure pattern which was observed was a bulging failure and no rupture failure was observed. Fiber length is important in strength because increased length of palm fiber bear the load imposed to soil specimen who results into increase in bearing capacity of soil specimen. Addition of palm fiber into the soil makes the soil homogenous or uniform because the number of fiber per unit volume will increase. But when the length of fiber increases with constant fiber inclusion then it reduces the homogeneity of soil and results in irregularity in the failure surface. This irregularity in failure surface gives strength to soil specimen because according to coulomb theory soil fails at an angle of obliquity. Hence it is concluded that the inclusion of fiber is not that effective as compared to

050

100150200250300350400

0 0.02 0.04 0.06 0.08

stre

ss k

Pa

strain ε

0.25%P.F

0.5%P.F

1%P.F

1.25%P.F

050

100150200250300350400450

0 0.02 0.04 0.06 0.08

stre

ss k

Pa

strain ε

0.25%p.f

0.5%P.F

1%P.F

1.25%P.F

050

100150200250300350400450

0 0.02 0.04 0.06 0.08

stre

ss k

Pa

strain ε

0.25% P.F

0.5% P.F

1% P.F

1.25% P.F



the length of fiber. Palm fibers good in the tensile property, when added to soil specimen, shows an effect upon failure surface direction and shear zone. This increase in tensile stress due to palm fiber cause high compression in the soil which results in soil to attain compressive stress in soil. Hence both the tensile stress and compressive stress starts acting in the soil specimen which leads to more ductility and strength in the soil specimen. From above curve, it is found that by adding palm fiber in the soil strength of soil increased by 58% as compared to virgin sample. But from figure 6, figure 7, figure 8 and figure 9 strength got decreased by 43% by adding bagasse ash to the soil with optimum of palm fiber. So the combination of both palm fiber and bagasse ash does not suitable for increasing the strength of soil specimen and soil stabilized only by using palm fiber gives higher strength.

Figure 6 Stress-strain curve with addition of optimum palm fiber and bagasse ash for 3 days curing



0

50

100

150

200

250

0 0.02 0.04 0.06 0.081%B.A+0.5%P.F 2%B.A+0.5%P.F

3%B.A+0.5%P.F 4%B.A+0.5%P.F

050

100150200250

0 0.01 0.02 0.03 0.04 0.05 0.06 0.07

1%BA+0.5%P.F 2%B.A+0.5%P.F

3%B.A+0.5%P.F 4%B.A+0.5%P.F




5. CONCLUSION Based on the above test result over palm fiber reinforced soil following conclusions was drawn:

In this study, an attempt was made by stabilizing soil with palm fiber and bagasse ash.

This paper investigated the palm fiber effects at 2cm length.

The optimum moisture content of the soil increases by the inclusion of palm fiber in the soil because palm fiber is good in water absorption property.

Maximum dry density decreases by increasing palm fiber content in the soil because palm fiber is light in weight.

It was observed that an optimum of 0.5% palm fiber showed peak strength in the soil by performing UCC test. The strength of reinforcing soil increased by 58% when compared to virgin sample.

By increasing fiber content in the soil, it results in the soil to be more ductile due to which it fails at the higher strain. Failure pattern which was observed was a bulging failure and there is no rupture failure.

The stress-strain curve for soil sample reinforced and stabilized with 0.5% optimum palm fiber and with 2% bagasse ash showed a result of strength reduced by 43% when compared with palm fiber reinforced soil.

Thus this paper examined that the soil strength is increased only with optimum of palm fiber and not with the combination of palm fiber and bagasse ash.

REFERENCES [1] A.R. Estabragh, A.T. Bordbar,A.A.Javadi (2012),“A study on the mechanical behavior of

a fiber clay composite with natural fiber”, Springer 31:501-510.

[2] Amin chegenizadeh, Hamid nikaraz (2012). “Effective parameter on strength of reinforced clayey sand”. International journal of material science, vol 2, no 1, pp 1-5.

[3] Andersland , O.B, and Khattak ,A S 1979. “ Shear strength of kaolinite / fiber soil mixtures “ International conference on soil reinforcement, Paris, France.

[4] J.Giridhar, Kishore, R.M.V.G.K.Rao (1986), “Moisture absorption characteristics of natural fiber composites”, Journal of reinforced plastic and composites, vol 5.

0

100

200

300

400

0 0.02 0.04 0.06 0.08 0.1

1% B.A +0.5% P.F 2% B.A +0.5%P.F

3% B.A +0.5% P.F 4% B.A+0.5%P.F



[5] Khushbu S. Gandhi(2014), “ Experimental study of surat region expansive soil modified using bagasse ash and wood ash”, International journal of IT and Engineering vol (2), no12.

[6] Koonnamas Punthutaecha et al (2006) studied the volume change behavior of expansive soil stabilized with recycled fiber ash and fiber.

[7] Manjunath K.R, Venugopal G, Rudresh A (2013), “Effect of random inclusion of sisal fiber on strength behavior of black cotton soil”, International journal of engineering research & technology vol (2), no 7.

[8] Mohammed Y Fattah, Firas A.Salnan, and Bestun, J.Naureeman (2010), “ A treatment of expansive soil using different additives”, Acta motaistica slovaca, vol 15, no 4.

[9] Murad Abu faraskh (2007), “Effect of soil moisture content and dry density on cohesive soil-geosynthetic interaction using large direct shear test”, Journal of materials in civil engineering ASCE 19:7(540).

[10] Omid azadegan, E.Akbari,Kaffash, M.J.Yaghoubi, G.R.Pourebrahim (2012), “ Laboratory study of the swelling cracking and mechanical characteristics of the palm fiber reinforcement clay”, EJGE vol (17).

[11] Patrick Khaoya barasa, Dr. Too, Kiptanui Jonah, S.M.Mulei (2013), “Stabilization of expansive clay using lime and sugarcane bagasse ash”. International journal of science and research vol (4), no-4.

[12] Rabindra Kumar Kar , Pradip Kumar Pradhan, Ashutosh Naik(2012), “Consolidation characteristics of fiber reinforced cohesive soil”, EJGE vol 17,Bund Z.

[13] Robin kaushik (2014), “An innovative technique of improving the CBR value of soil using hair fiber”, Global journal of engineering science and researches, vol 1, no 4.

[14] S.M.Marandi, M.H.Bagheripour,R.Rahgozar and H.Zare (2008), “Strength and ductility of randomly distributed palm fibers reinforced silty sand soil”, American journal of applied science vol (5), no.3, pp.209-220

[15] Shahram pourabakar, Afshin Asadi, Bujang B.K. Huat (2015), “Stabilization of clayey soil using ultrafine palm oil fuel ash (POFA) and cement, Transportation geotechnics, ELSEVIER, vol (3), pp 24-35.

[16] Soundara, B, Senthil kumar, K.P (2015), “Effect of fibers on properties of clay”, Journal of Geotechnical engineering, (IJEAS) vol (2), no. 5, pp 123-128.

[17] Tonghua zhang, Min Guo, Lan Cheng (2014), “Investigation on the structure and properties of palm leaf sheath fiber”, Springer DOI 10.

[18] Viswasnadham, B.V.S, Phanikumar, B.R. and Mukharjee (2009), “Swelling behavior of a geofiber reinforced expansive soil”, Geotextile and geomembrane, 27(1), 73-76.

[19] K Sampath Kumar, U M Praveen, A Prathyusha, V Akhila, P Sasidhar, A Comprehensive Study On Partial Replacement of Cement with Sugarcane Bagasse Ash, Rice Husk Ash & Stone Dust, International Journal of Civil Engineering and Technology, 7(3), 2016, pp. 163–172.

experimental study on stren gth … · consolidation settlement of fiber reinforced compacted clay....

Documents