Numerical and experimental analyses for bearing capacity of rigid strip footing subjected to eccentric load

Abstract

A footing may get an eccentric load caused by earthquake or wind, thus the bearing capacity of footing subjected to eccentric load become a fundamental geotechnical problem. The conventional limit equilibrium method used for this problem usually evaluates the material properties only by its final strength. But the classical finite element method (FEM) does not necessarily provide a clear collapse mechanism associated with the yield condition of elements. To overcome these defects, a numerical procedure is proposed to create an explicit collapse mode combining a modified smeared shear band approach with a modified initial stress method. To understand the practical performance of sand foundation and verify the performance of the proposed procedure applied to the practical problems, the computing results were compared with the laboratory model tests results and some conventional solutions. Furthermore, because the proposed numerical procedure employs a simple elasto-plastic model which requires a small number of soil parameters, it may be applied directly to practical design works.

Keywords

bearing capacity / eccentric load / slip surface / shear band / finite element method / model test

References

[1] MeyerhofG G. The bearing capacity of footings under eccentric and inclined loads [C]. Proceedings 3rd International Conference Soil Mechanics Foundations Engineering, 1953, Zurich, Organizing Committee ICOSOMEF: 440-445

[2] PekerA, SalenconJ. Seismic bearing capacity of shallow strip foundations on clay soils [C]. Proceedings of International Workshop on Seismology and Earthquake Engineering, Mexico, 1991297-304

[3] ButterfieldR, GottardiG. A complete three-dimentional failure envelope for shallow footing on sand [J]. Géotechnique, 1994, 44(1): 181-184

[4] MartinC MPhysical and numerical modeling of offshore foundations under combined loads [D], 1994, UK, University of Oxford

[5] MaugeriM, MusumeciG, NovitaD, TaylorC A. Shaking table test of failure of a shallow foundation subjected to an eccentric load [J]. Soil Dynamics and Earthquake Engineering, 2000, 22: 435-444

[6] PatraC R, DasB M, BhoiM, ShinE C. Eccentrically loaded strip foundation on geogrid-reinforced sand [J]. Geotextiles and Geomemberanes, 2006, 24: 254-259

[7] PrakashS, SaranS. Bearing capacity of eccentrically loaded footings [J]. Journal of the Soil Mechanics and Foundations Division: ASCE, 1971, 97(1): 95-117

[8] MichalowskiR L, YouL. Effective width rule in calculations of bearing capacity of shallow footings [J]. Computers and Geotechnics, 1998, 23: 237-253

[9] HoulsbyG T, PuzrinA M. The bearing capacity of a strip footing on clay under combined loading [C]. Proceedings of the Royal Society of London: Series A. London, 1999, 455(1983): 893-916

[10] DormieuxL, PeckerA. Seismic bearing capacity of foundation on cohesionless soil [J]. Journal of Geotechnical Engineering, 1995, 121(3): 300-303

[11] YangX-l, YinJ-h, LiLiang. Influence of a nonlinear failure criterion on the bearing capacity of a strip footing resting on rock mass using a lower bound approach [J]. Canandian Geotechnical Journal, 2003, 40(3): 702-707

[12] YangX-l, SuiZ-rong. Seismic failure mechanisms for loaded slopes with associated and nonassociated flow rules [J]. J Cent South Univ Technol, 2008, 15: 276-279

[13] MassinD S Y A, SoubraA H. Numerical simulations for the bearing capacity of strip footings [J] Conference Proceedings. Advances in Shallow Foundations, ASCE, 2007, 234(5): 1-10

[14] de BorstR, VermeerP A. Possibilities and limitations of finite elements for limit analysis [J]. Géotechnique, 1984, 34(2): 199-210

[15] FrydmanS, BurdH J. Numerical studies of bearing capacity factor N? [J]. Journal of Geotechnical and Geoenvironmental Engineering: ASCE, 1997, 123(1): 20-29

[16] HuY, RandolphM F. Deep penetration of shallow foundations on non-homogeneous soil [J]. Soils and Foundations, 1998, 38(1): 241-246

[17] ZienkiewiczO C, HuangM. Localization problems in plasticity using finite elements with adaptive remeshing [J]. International Journal for Numerical and Analytical Methods in Geomechanics, 1995, 19(2): 127-148

[18] LuL, AraiK, WangZ-jian. Laboratory model test and numerical analysis of bearing capacity of rigid strip footing [J]. Journal of Applied Mechanics: JSCE, 2007, 10: 351-362

[19] Lu Liang AraiK, WangZ-j, NishiyamaR. Laboratory model test and numerical analysis of bearing capacity of rigid strip footing on slope [J]. Journal of Applied Mechanics: JSCE, 2008, 11: 399-410

[20] ZienkiewiczO C, ValliappanS, KingI P. Elastoplastic solutions of engineering problems “initial stress”, finite element approach [J]. International Journal for Numerical Methods in Engineering, 1969, 1: 75-100

[21] PietruszczakS, MrozZ. Finite element analysis of deformation of strain-softening materials [J]. International Journal for Numerical Methods in Engineering, 1981, 17: 327-334

[22] NayakG C, ZienkiewiczO C. Elasto-plastic stress analysis: A generalization for various constitutive relations including strain softening [J]. International Journal for Numerical Methods in Engineering, 1972, 5: 113-135