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  • International Journal of Civil Engineering and Technology (IJCIET), ISSN 0976 – 6308(Print), ISSN 0976 – 6316(Online) Volume 4, Issue 2, March - April (2013), © IAEME189FRAMEWORK FOR ASSESSMENT OF SHEAR STRENGTHPARAMETERS OF RESIDUAL TROPICAL SOILSNagendra Prasad.K1, Sivaramulu Naidu.D2, Harsha Vardhan Reddy. M3, Chandra.B41Professor, Dept. of Civil Engineering, SV University, Tirupati, India,2Research Scholar, Dept. of Civil Engineering, SV University, Tirupati, India.3Former under-graduate student, Dept. of Civil Engineering, SV University, Tirupati, India.4Post-graduate student, Dept. of Civil Engineering, SV University, Tirupati, India.ABSTRACTFailure of soil may cause collapse of structures resulting in loss of lives and economicdamage. Most geotechnical instability problems including failure of soil are associated withshear failure. Shear strength is one of the most important properties for design of engineeringstructures and also one of the most difficult to evaluate. In order to determine the shearstrength parameters that govern shear strength, such as angle of internal friction andcohesion, typical laboratory tests such as the direct shear test and triaxial test are used.However, these laboratory tests have some shortcomings regarding sample collection such aslack of in-situ conditions and difficulties for obtaining undisturbed soil samples. In-situtesting methods are also used to determine the shear strength of soil such as the Vane ShearTest, the Standard Penetration Test and the Cone Penetration Test. However, these testsestimate the shear strength of the soil with appropriate empirical correlations that have a widemargin of error. Traditional testing methods to acquire the shear strength parameters areexpensive, complicated, time consuming, and require extreme care during the process ofcollecting, storing, transporting and preserving samples. The objective of this paper is todevelop a phenomenological model that could be used to predict the shear strengthparameters from their index properties (liquid limit) and other engineering properties(specific gravity, void ratio, maximum dry density), which are relatively easy to determine.The validity of the method was proven by determining shear strength parameters for varioustypes of soils and by comparing them with the results taken from a conventional testingmethod. This could be used to rapidly estimate cohesion and friction angle in situationswhere either the good quality samples or the equipment needed to conduct such tests are notavailable.INTERNATIONAL JOURNAL OF CIVIL ENGINEERING ANDTECHNOLOGY (IJCIET)ISSN 0976 – 6308 (Print)ISSN 0976 – 6316(Online)Volume 4, Issue 2, March - April (2013), pp. 189-207© IAEME: www.iaeme.com/ijciet.aspJournal Impact Factor (2013): 5.3277 (Calculated by GISI)www.jifactor.comIJCIET© IAEME
  • International Journal of Civil Engineering and Technology (IJCIET), ISSN 0976 – 6308(Print), ISSN 0976 – 6316(Online) Volume 4, Issue 2, March - April (2013), © IAEME190Keywords: shear strength parameters, bulk modulus, normal compression line, triaxialtest, volumetric strain, maximum dry density.1. INTRODUCTIONThe structural strength is primarily a function of shear strength of soil. Soil failureusually occurs in the form of “shearing” along internal surface within the soil. Shearstrength is soils’ ability to resist sliding along internal surfaces within the soil mass. Thestrength of clayey soil is influenced by compaction energy, optimum moisture content,dry density, percentage of fines, degree of saturation, consistency limits, cohesion andfrictional resistance between the particles. According to Mohr’s theory, a soil mass willfail when the shearing stress on the failure plane, which is a definite function of thenormal stress acting on that plane, is greater than the shear resistance of the soil i.e. S = f(σn). The shearing strength of a soil is represented by the following Mohr-Coulomb’sequation,S = c + σn tan фWhere,S = Shear stress at failurec = cohesion i.e. the resistance of soil particles to displacement due to intermolecularattraction and surface tension of the held waterσn = Normal stressф = Angle of internal friction.The angle of internal friction depends upon dry density, particle size distribution,shape of particles, surface texture, and water content. It is directly proportional to theapplied normal force acting between the particles. In clayey soils, partially saturated soils,and cemented soils, the individual soil particles are bonded together. This is anothersource of the shear strength of soil which is independent from the normal force, calledcohesion. Cohesion depends upon size of clayey particles, type of clay minerals, valencebond between particles, water content, and proportion of the clay. In geotechnical designpractice, two important considerations that need careful examination are whetherconstruction will cause deformation of the soil and /or instability due to shear failure. Anengineer has to ensure that the structure is safe against shear failure in the soil thatsupports it and does not undergo excessive settlement. Therefore knowledge about thestress-strain behaviour, deformation and shear strength of the soil is essential. Theseconsiderations are more complicated and challenging when dealing with clayey soil,which is known to be highly deformable and have low shear strength. It can bedetermined either in the field or in the laboratory, or both. The tests employed in thelaboratory may include unconfined compression test, triaxial test, laboratory vane, directshear box and direct simple shear test. In situ tests are normally conducted to test thevalidity of the laboratory tests and for design purposes. However, these laboratory testshave some shortcomings regarding sample conditions such as lack of in-situ conditions
  • International Journal of Civil Engineering and Technology (IJCIET), ISSN 0976 – 6308(Print), ISSN 0976 – 6316(Online) Volume 4, Issue 2, March - April (2013), © IAEME191and difficulties for obtaining undisturbed soil samples apart from difficulties associatedwith simulating drainage conditions appropriately. Insitu tests available include fieldvane, standard penetration test, cone penetration test, and piezocone and pressure meter.However, these tests estimate the shear strength of the soil with appropriate empiricalcorrelations that have a wide margin of error. The present work aims at evaluating theshear strength parameters of soil at a state of maximum dry density taking intoconsideration its liquid limit and Proctors maximum dry density since soil is compactedto its maximum dry density in almost all earth structures.2. BACKGROUND INFORMATIONInvestigation carried out by Burak (2008) has established correlation betweenindex properties and shear strength parameters of normally consolidated clays bystatistical and neural approaches. Amin (1997) made studies to predict and determineundrained shear strength, a very important parameter in design practice, for Klang clay,Malaysia. Shear strength is determined using field and laboratory vane shear andrecompression method utilizing the direct simple shear apparatus. Analysis of the triaxialtest results of Satija (1978) reveals some nonlinearity in the shear stress versus matricsuction failure envelope (Fredlund et al. 2000). Fredlund and Vanapalli (2000) in a recentstudy have provided comparisons between the measured and predicted values ofunsaturated shear strength using the shear strength functions published in the literature.Comparisons were provided both for low suction range (i.e., 0 to 1,500 kPa) as well aslarge suction range (0 to 10,000 kPa or higher).Vanapalli et al. (2001) predicted the shear strength of an unsaturated soil with asemi-empirical shear strength function developed at the University of Saskatchewan bothfor low and as well as large suction ranges. Rajeev Jain et al. (2010) presented anartificial neural network technique to predict the shear strength parameters of mediumcompressibility soil, which influenced by basic properties of soil in unconsolidatedundrained conditions. Kamil Kayabali (2011) investigated the shear strengths at plasticlimit and liquid limit by reappraising a large body of shear strength and soil consistencydata. . If the shear strength at plastic limit and liquid limit are set properly, the undrainedshear strength of remolded soils at any water content between Plastic limit and liquidlimit can be determined easily. Erfan Hosseini (2012) studied shear strength parametersby using grading test, Atterberg limits, compression, direct shear and consolidation.Soil StateIt is widely known that the stress and strain are inseparable for all materials underloading. The stress the particulate materials experience depends on the associated strainand vice versa. Accordingly, an attempt has been made to analyse the mobilisation ofshear strength in relation to the volumetric strain, the sample experiences to exhibitmaximum resistance. The volumetric strain is reckoned with reference to the possibleloose state in order to arrive at the current state. It is the current state of soil thatdetermines the shear strength of soils irrespective of the stress path the soil follows toreach the current state as demonstrated in the Figure 1. At (a) the soil is under a pressureof 1 kPa and at (b) the soil is at maximum dry density.
  • International Journal of Civil Engineering and Technology (IJCIET), ISSN 0976 – 6308(Print), ISSN 0976 – 6316(Online) Volume 4, Issue 2, March - April (2013), © IAEME192Figure 1: Depiction of Soil StateBulk ModulusBulk modulus (K) of a substance measures the substances resistance to uniformcompression. It is defined as the ratio of the infinitesimal pressure increase to the resultingrelative decrease of the volume.The bulk modulus K>0 can be formally defined by the equation,Where,P = PressureV = Volume= Derivative of pressure with respect to volume.3. EXPERIMENTAL INVESTIGATION3.1 IntroductionThe study area lies to the extreme south of Andhra Pradesh state (India)approximately between 12° 37 - 14° 8 north latitudes and 78° 3 - 79° 55 east longitudes.The experimental methods of different laboratory investigations are carried out on thetropical residual soils of Tirupati region.3.2 Details of the Experimental InvestigationThe present experimental investigation is carefully planned to understand the behaviorof tropical residual soils. The experimental program involves determination of the followingaspects.Basic propertiesCompaction propertiesUndrained triaxial compression testAll the tests were conducted as per the relevant provisions stipulated in Bureau of IndianStandards.
  • International Journal of Civil Engineering and Technology (IJCIET), ISSN 0976 – 6308(Print), ISSN 0976 – 6316(Online) Volume 4, Issue 2, March - April (2013), © IAEME1933.3 Soils TestedThe soils considered in the present investigation have been obtained from thesurroundings of Tirupati region. The location of soil samples can be seen from Figures 2 and3. The details of locations of sampling are shown in Table 1. Laboratory data of the samples1 to 15 are used to analyze and predict the correlation among c, ф and bulk modulus (K) ofvarious soil samples. Data of samples A, B and C obtained from the laboratory are examinedto verify the accuracy of prediction in a phenomenological model. These soils are residual innature, which are deposited at the place of formation.Figure 2: Sample locations at Tirupati region in India mapFigure 3: Detailed sample locations at Tirupati region
  • International Journal of Civil Engineering and Technology (IJCIET), ISSN 0976 – 6308(Print), ISSN 0976 – 6316(Online) Volume 4, Issue 2, March - April (2013), © IAEME194Table 1: Soil Sample LocationsS.No Sample Location1 Beerakuppam (Village)2 Gongutapalli (Village)3 RC Kandriga4 Nagari5 Avalkonda6 Renigunta by-pass7 Tiruchanur8 Kottramangal(village)9 Pillaripattu10 Padmavathipuram11 Nagari Station12 Dhodlamitta (village)13 Kandriga(village)14 Daminedu15 PadmavatipuramA K.T.RoadB Kothapalem layoutC Padipeta3.4 Collection of SamplesSoil samples considered represent wide spectrum of typical soils encountered inpractice, ranging from predominantly clayey sand to clay with low to high compressibility.Soil samples have been collected by exercising necessary care to see that the naturalconstituents are represented and the same were transported to geotechnical engineeringlaboratory. The samples were air dried and stored in air tight containers for use in rest of theinvestigation.
  • International Journal of Civil Engineering and Technology (IJCIET), ISSN 0976 – 6308(Print), ISSN 0976 – 6316(Online) Volume 4, Issue 2, March - April (2013), © IAEME1953.5 Properties of SoilsIndex properties and the compaction properties for all the samples including A, B and Care presented in Tables 2 and 3. It may be seen that most of the soils represent clayey sand(SC) and few samples fall under clay with intermediate and high compressibility (CI, CH).The liquid limit values for the samples considered ranges from 31% to 67% and the plasticlimit varies from 14% to 22%. The fine fraction ranges from 29% to 83% which is typical forthe soils encountered in practice in this region. The cohesion values ranges from 28.70 kPa to74.80 kPa and angle of internal friction ranges from 14.25oto 23.37o.4 ANALYSIS OF TEST RESULTSThe usual object of detailed experimental investigation will be to propose amechanistic approach for understanding the behavior of materials tested in a coherent mannerby properly analyzing the observed behavior. Accordingly a detailed analysis of test resultsis presented in the following section.4.1 Triaxial test dataTriaxial compression tests have been conducted on samples 1 through 15 and the testresults are depicted from Figures 4 to 21. Mohr’s circles are drawn for soil samples 1 to 8 asshown in Figures 22 to 29. Similar Mohr circles can be drawn for other soil samples also. Thevalues of c and ф thus determined from the Mohr’s circle approach are represented in Tables2 and 3. The stress-strain response of the sample is noticed to be typical with greaterdeviatoric stress for greater confining pressures. The shear strains experienced by the samplesseem to be related to the degree of compression to which the samples is subjected.Figure 4: Deviatoric stress verses strainfor sample 1Figure 5: Deviatoric stress verses strainfor sample 2
  • International Journal of Civil Engineering and Technology (IJCIET), ISSN 0976 – 6308(Print), ISSN 0976 – 6316(Online) Volume 4, Issue 2, March - April (2013), © IAEME196Figure 6: Deviatoric stress verses strainfor sample 3Figure 7: Deviatoric stress verses strainfor sample 4Figure 8: Deviatoric stress verses strainfor sample 5Figure 9: Deviatoric stress verses strain forsample 6
  • International Journal of Civil Engineering and Technology (IJCIET), ISSN 0976 – 6308(Print), ISSN 0976 – 6316(Online) Volume 4, Issue 2, March - April (2013), © IAEME197Figure 10: Deviatoric stress verses strainfor sample 7Figure 11: Deviatoric stress verses strainfor sample 8Figure 12: Deviatoric stress verses strainfor sample 9Figure 13: Deviatoric stress verses strainfor sample 10
  • International Journal of Civil Engineering and Technology (IJCIET), ISSN 0976 – 6308(Print), ISSN 0976 – 6316(Online) Volume 4, Issue 2, March - April (2013), © IAEME198Figure 15: Deviatoric stress verses strainfor sample 12Figure 14: Deviatoric stress verses strainfor sample 11Figure 16: Deviatoric stress verses strainfor sample 13Figure 17: Deviatoric stress verses strainfor sample 14
  • International Journal of Civil Engineering and Technology (IJCIET), ISSN 0976 – 6308(Print), ISSN 0976 – 6316(Online) Volume 4, Issue 2, March - April (2013), © IAEME199Figure 19: Deviatoric stress verses strainfor sample AFigure 18: Deviatoric stress verses strainfor sample 15Figure 20: Deviatoric stress verses strainfor sample BFigure 21: Deviatoric stress verses strainfor sample C
  • International Journal of Civil Engineering and Technology (IJCIET), ISSN 0976 – 6308(Print), ISSN 0976 – 6316(Online) Volume 4, Issue 2, March - April (2013), © IAEME200Figure 23: Mohrs circle approach todetermine c and ф for sample 2Figure 22: Mohrs circle approach todetermine c and ф for sample 1Figure 24: Mohrs circle approach todetermine c and ф for sample 3Figure 25: Mohrs circle approach todetermine c and ф for sample 4
  • International Journal of Civil Engineering and Technology (IJCIET), ISSN 0976 – 6308(Print), ISSN 0976 – 6316(Online) Volume 4, Issue 2, March - April (2013), © IAEME201Figure 26: Mohrs circle approach todetermine c and ф for sample 5Figure 27: Mohrs circle approach todetermine c and ф for sample 6Figure 28: Mohrs circle approach todetermine c and ф for sample 7Figure 29: Mohrs circle approach todetermine c and ф for sample 8
  • International Journal of Civil Engineering and Technology (IJCIET), ISSN 0976 – 6308(Print), ISSN 0976 – 6316(Online) Volume 4, Issue 2, March - April (2013), © IAEME202Table 2: Soil PropertiesSl.No:DescriptionValuesSample1Sample2Sample3Sample4Sample5Sample6Sample7Sample8Sample91 Gravel (%) 2 2.4 4.2 3.30 11.2 0.40 3.20 16.87 7.302 Sand (%) 26.6 65.2 49.4 28.00 61.4 36.8 53.20 33.18 42.303 Silt+Clay (%) 71.4 32.4 46.4 68.70 27.4 62.8 43.6 49.64 50.404 0.425 mm Size (%) 83.2 46.4 55.2 29.8 29.8 75.2 63.4 58.21 66.205 Liquid Limit, WL (%) 31 32 36 41 44 45 46 49 526 Plastic Limit, PL (%) 14 17 18 16.00 19 20 17 22 187 Plasticity Index, PI (%) 17 15 18 25 25 25 29 27 348 IS Classification CL SC CI CI SC CI SC CI CH9 Free Swell Index (%) 25 25 20 45.00 45 55 60 80 7010 Degree of Expansion Low Low Low Low Low Medium Medium LowMedium13Optimum moisture content,(%)13.75 13.98 14.9 16.05 16.74 16.97 17.43 17.89 18.5814Maximum dry density, γd(kN/m3)18.54 18.47 18.13 17.71 17.48 17.40 17.24 17.09 16.87Shear strength parameters15 Cohesion, C in kPa28.70 29.70 39.40 49.20 55.90 54.50 47.40 59.00 61.2016Angle of internal friction,Φ in degrees14.25 15.12 16.09 16.88 17.84 18.24 19.90 19.67 20.93
  • International Journal of Civil Engineering and Technology (IJCIET), ISSN 0976 – 6308(Print), ISSN 0976 – 6316(Online) Volume 4, Issue 2, March - April (2013), © IAEME203Table 3: Soil PropertiesSl.No:DescriptionValuesSample10Sample11Sample12Sample13Sample14Sample15SampleASampleBSampleC1 Gravel (%) 7.75 6 3.80 3.2 1.8 3.4 3.9 16.87 10.252 Sand (%) 51.50 71.9 12.60 18.8 59.7 26.8 58.1 33.18 59.33 Silt+Clay (%) 40.75 22.1 62.6 78 38.5 69.8 38 49.94 30.54 0.425 mm Size (%) 50 30.7 41 80 50.1 83.2 52 58.21 48.105 Liquid Limit, WL (%) 54 57 59 60 64 67 38 50 636 Plastic Limit, PL (%) 19 18 19 20 20 15 16 22 207 Plasticity Index, PI (%) 35 39 40 40 44 52 22 28 438 IS Classification SC SC CH CH SC CH SC CI SC9 Free Swell Index (%) 80 60 75 80 105 140 50 80 8010 Degree of Expansion Medium Medium Medium Medium High HighMediumMediumMedium13Optimum moisture content,(%)19.04 19.73 20.19 20.42 21.34 22.03 15.36 18.12 21.1114Maximum dry density, γd(kN/m3)16.72 16.51 16.37 16.30 16.03 15.80 17.96 17.02 16.10Shear strength parameters15 Cohesion, C in kPa64.00 65.50 64.20 68.70 71.80 74.40 41.50 55.50 74.8016Angle of internal friction, Φin degrees 21.23 21.86 23.29 22.41 23.37 23.35 16.94 18.42 22.044.2 Behaviour with respect to Normal Compression Line (NCL)An attempt has been made to examine the compression behavior with respect toNormal Compression Line (NCL) for which the equation given by Nagaraj et.al. (1994) asreproduced below has been adopted.(1)Where,e = Void ratio at a given pressure of σv’eL = Void ratio corresponding to liquid limit.log276.023.1 vLeeσ−=
  • International Journal of Civil Engineering and Technology (IJCIET), ISSN 0976 – 6308(Print), ISSN 0976 – 6316(Online) Volume 4, Issue 2, March - April (2013), © IAEME2044.3 Determination of Void RatioVoid ratio corresponding to liquid limit will be minimum and can be determined as theproduct of specific gravity (G) and liquid limit (WL). When the soil is compacted to its maximumdry density, void ratio decreases accordingly which can be determined from the equation,(2)Where,= Maximum dry densityG = Specific gravity of soil= Unit weight of watere = Void ratio at a given pressure of σv’σvmax, pressure corresponding to maximum dry density is now determined from equation (1), bysubstituting e and eL values. The void ratio (eo) in the loosest state under a pressure of 1kPa isdetermined from equation (1) for all the soil samples knowing their liquid limits.4.4 Volumetric StrainThe volumetric strain (ϵv) can now be determined from the equation,Where,eo = void ratio under pressure of 1kPae = void ratio at a state of maximum dry density4.5 Bulk ModulusBulk modulus (K) can be obtained as the ratio of the infinitesimal pressure increase tovolumetric strain,dP for all the 15 soil samples (1-15) can be evaluated as the difference of the pressure betweenloosest state (corresponding to a normal stress of 1 kPa) and pre-compression stress (σvmax,referred to a normal compression line of natural state of soil).4.6 Bulk Modulus versus c and фA graph of bulk modulus (K) versus c and bulk modulus (K) versus ф is plotted asdepicted in Figures 30 and 31 respectively. Experimental results usually show small deviationsand a best fit straight line from plotted data is normally drawn to establish a definite relation. Acorrelation of 97.60% and 96.10% are obtained for bulk modulus (K) versus cohesion (c) andbulk modulus (K) versus angle of internal friction (ф) respectively.The equation thus obtained for bulk modulus (K) versus c is as follows:c = 0.034K - 13.46 (5)And for bulk modulus (K) versus ф it is:ф = 0.007K + 4.812 (6)
  • International Journal of Civil Engineering and Technology (IJCIET), ISSN 0976 – 6308(Print), ISSN 0976 – 6316(Online) Volume 4, Issue 2, March - April (2013), © IAEME205Figure 30: Bulk modulus (K) versus Cohesion (c)Figure 31: Bulk modulus (K) versus Angle of internal friction (ф)
  • International Journal of Civil Engineering and Technology (IJCIET), ISSN 0976 – 6308(Print), ISSN 0976 – 6316(Online) Volume 4, Issue 2, March - April (2013), © IAEME2065 PREDICTION OF SHEAR STRENGTH PARAMETERS (C & Ф)The validity of the present investigation can be checked by determining shear strengthparameters of the samples A, B and C. The shear strength parameters c and ф are determinedfrom the conventional triaxial test to check the accuracy of predicted data. Using liquid limit,void ratio in loosest state under a pressure of 1 kPa (eo), is determined by equation (1). Voidratio at maximum dry density (e), for samples A, B and C are determined from equation (2).Now volumetric strain and bulk modulus are determined from equations (3) and (4)respectively. From bulk modulus, the cohesion(c) values for each sample A, B and C areobtained using equation (5). Similarly the angle of internal friction (ф) for these samples isobtained from equation (6).5.1 Accuracy in PredictionData thus predicted is compared with the laboratory data obtained from conventionaltriaxial test. It is observed that the accuracy of prediction in the evaluation of both c and фaccounts to about 96%.6. CONCLUDING REMARKSThe objective of this study is to suggest a phenomenological model to correlate liquidlimit, maximum dry density with shear strength parameters such as cohesion and angle ofinternal friction.1) The values of cohesion (c) and angle of internal friction (ф) alters with the state ofsoil or simply, they represent the state of soil.2) Void ratio decreases when the soil is compacted from loosest state to its maximumdry density.3) Both cohesion (c) and angle of internal friction (ф) increases with increase in bulkmodulus (K).4) Relation between bulk modulus (K) and cohesion (c) is almost linear.5) Also, the relation between bulk modulus (K) and angle of internal friction (ф) isalmost linear.6) Increase in cohesion (c) is more when compared to increase in angle of internalfriction (ф) with increase in bulk modulus.7) The present state of soil determines its shear strength irrespective of the pathfollowed.8) The compacted soil state lies on left hand side of the Normal Compression Line andhence the state is quite akin to over-consolidated state.9) The volumetric strain to which the sample undergoes depends on the stress which inturn depends on the compaction energy imparted.10) Accuracy of prediction in the evaluation of both cohesion (c) and angle of internalfriction (ф) accounts to about 96%.
  • International Journal of Civil Engineering and Technology (IJCIET), ISSN 0976 – 6308(Print), ISSN 0976 – 6316(Online) Volume 4, Issue 2, March - April (2013), © IAEME207REFERENCES[1] Amin (1997), “Prediction and Determination of Undrained Shear Strength of SoftClay”, Pertanika J. Sci. & Techno! 5(1): 111-126.[2] Burak (2008), “Shear strength estimation of plastic clays with statistical and neuralapproaches”, Journal of Building and Environment, vol. 43.[3] Fredlund (1987), “Nonlinearity of strength envelope for unsaturated soils, proceedingsof the 6th international conference on expansive soils”, New Delhi.[4] Fredlund, D.G. and Vanapalli (2000), “Comparison of different procedures to predictunsaturated soil shear strength”, ASTM Proceedings, Unsaturated Soils, Geo-Denver2000.[5] Erfan Hosseini, Mohammad K. Alizadeh, and Amir Mesbah (2012), “Evaluation ofShear Strength Parameters of Amended Loess Using Common Admixtures in Gorgan,Iran”, International Journal of Science, Engineering and Technology.[6] Kamil Kayabali (2011), “Assessment of Shear Strength at Consistency Limits - AReappraisal”, Vol. 16, EJGE Journal.[7] Nagaraj,T.S. & Srinivasa Murthy B.R. and Vatsala, A. (1994), “Analysis and Predictionof Soil Behavior”, Wiley Eastern Journal, New Delhi.[8] Rajeev Jain and Pradeep Kumar Jain (2010), “Computational approach to predict soilshear strength”, International Journal of Engineering Science and Technology.[9] Satija B. S. (1978), “Shear behavior of partly saturated soils”, Ph.D. thesis, IndianInstitute of Technology, Delhi, India.[10] Vanapalli (2001), “Predicting the shear strength of an unsaturated soil”, The CanadianGeotechnical Society Journal.[11] Ercan Serif Kaya, Takuro Katayama and Toshitaka Yamao, “Seismic Characteristics OfThe Folded Cantilever Shear Structure”, International Journal of Civil Engineering &Technology (IJCIET), Volume 4, Issue 2, 2013, pp. 58 - 79, ISSN Print: 0976 – 6308,ISSN Online: 0976 – 6316.[11] M. Alhassan and I. L. Boiko, “Effect of Vertical Cross-Sectional Shape of Foundationand Soil Reinforcement on Settlement and Bearing Capacity of Soils”, InternationalJournal of Civil Engineering & Technology (IJCIET), Volume 4, Issue 2, 2013,pp. 80 - 88, ISSN Print: 0976 – 6308, ISSN Online: 0976 – 6316.