Reliability-Based Analysis of Strip Footings Using Response Surface Methodology
Publication: International Journal of Geomechanics
Volume 8, Issue 2
Abstract
A reliability-based analysis of a strip foundation subjected to a central vertical load is presented. Both the ultimate and the serviceability limit states are considered. Two deterministic models based on numerical simulations are used. The first one computes the ultimate bearing capacity of the foundation and the second one calculates the footing displacement due to an applied load. The response surface methodology is utilized for the assessment of the Hasofer–Lind reliability indexes. Only the soil shear strength parameters are considered as random variables while studying the ultimate limit state. Also, the randomness of only the soil elastic properties is taken into account in the serviceability limit state. The assumption of uncorrelated variables was found to be conservative in comparison to the one of negatively correlated variables. The failure probability of the ultimate limit state was highly influenced by the variability of the angle of internal friction. However, for the serviceability limit state, the accurate determination of the uncertainties of the Young's modulus was found to be very important in obtaining reliable probabilistic results. Finally, the computation of the system failure probability involving both ultimate and serviceability limit states was presented and discussed.
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Acknowledgments
The writers would like to thank the Lebanese National Council for Scientific Research (CNRSL) and the French organization EGIDE for providing the financial support for this research.
References
Baecher, G., and Christian, J. (2003). Reliability and statistics in geotechnical engineering, Wiley, U.K.
Bauer, J., and Pula, W. (2000). “Reliability with respect to settlement limit-states of shallow foundations on linearly-deformable subsoil.” Comput. Geotech., 26, 281–308.
Cherubini, C. (2000). “Reliability evaluation of shallow foundation bearing capacity on , soils.” Can. Geotech. J., 37, 264–269.
Ditlevsen, O. (1981). Uncertainty modelling: With applications to multidimensional civil engineering systems, McGraw-Hill, New York.
Fenton, G. A., and Griffiths, D. V. (2002). “Probabilistic foundation settlement on spatially random soil.” J. Geotech. Geoenviron. Eng., 128(5), 381–390.
Fenton, G. A., and Griffiths, D. V. (2003). “Bearing capacity prediction of spatially random soils.” Can. Geotech. J., 40, 54–65.
Fenton, G. A., and Griffiths, D. V. (2005). “Three-dimensional probabilistic foundation settlement.” J. Geotech. Geoenviron. Eng., 131(2), 232–239.
. (1993). Fast Lagrangian analysis of continua, ITASCA Consulting Group, Inc., Minneapolis.
Griffiths, D. V., and Fenton, G. A. (2001). “Bearing capacity of spatially random soil: the undrained clay Prandtl problem revisited.” Geotechnique, 51(4), 351–359.
Griffiths, D. V., Fenton, G. A., and Manoharan, N. (2002). “Bearing capacity of rough rigid strip footing on cohesive soil: Probabilistic study.” J. Geotech. Geoenviron. Eng., 128(9), 743–755.
Harr, M. E. (1987). Reliability-based design in civil engineering, McGraw-Hill, New York.
Hasofer, A. M., and Lind, N. C. (1974). “Exact and invariant second-moment code format.” J. Engrg. Mech. Div., 100(1), 111–121.
Lemaire, M. (2005). Fiabilité des structures, Hermès, Lavoisier, Paris (in French).
Low, B. K. (2005). “Reliability-based design applied to retaining walls.” Geotechnique, 55(1), 63–75.
Low, B. K., and Phoon, K. K. (2002). “Practical first-order reliability computations using spreadsheet.” Proc., Probabilistics in Geotechnics: Technical and Economic Risk Estimation, Verlag Gluckauf GmbH. Essen, Graz, Austria, 39–46.
Low, B. K., and Tang, W. H. (1997a). “Efficient reliability evaluation using spreadsheet.” J. Eng. Mech., 123(7), 749–752.
Low, B. K., and Tang, W. H. (1997b). “Reliability analysis of reinforced embankments on soft ground.” Can. Geotech. J., 34, 672–685.
Low, B. K., and Tang, W. H. (2004). “Reliability analysis using object-oriented constrained optimization.” Struct. Safety, 26, 68–89.
Lumb, P. (1970). “Safety factors and the probability distribution of soil strength.” Can. Geotech. J., 7, 225–242.
Nour, A., Slimani, A., and Laouami, N. (2002). “Foundation settlement statistics via finite element analysis.” Comput. Geotech., 29, 641–672.
Phoon, K.-K., and Kulhawy, F. H. (1999). “Evaluation of geotechnical property variability.” Can. Geotech. J., 36, 625–639.
Popescu, R., Deodatis, G., and Nobahar, A. (2005). “Effect of random heterogeneity of soil properties on bearing capacity.” Probab. Eng. Mech., 20, 324–341.
Przewlocki, J. (2005). “A stochastic approach to the problem of bearing capacity by the method of characteristics.” Comput. Geotech., 32, 370–376.
Tandjiria, V., Teh, C. I., and Low, B. K. (2000). “Reliability analysis of laterally loaded piles using response surface methods.” Struct. Safety, 22, 335–355.
Wolff, T. H. (1985). “Analysis and design of embankment dam slopes: A probabilistic approach.” Ph.D. thesis, Purdue Univ., Lafayette, Ind.
Yin, J.-H., Wang, Y.-J., and Selvadurai, P. S. (2001). “Influence of nonassociativity on the bearing capacity of a strip footing.” J. Geotech. Geoenviron. Eng., 127(11), 985–989.
Youssef Abdel Massih, D. S., Soubra, A.-H., and Low, B. K. (2008). “Reliability-based analysis and design of strip footings against bearing capacity failure.” J. Geotech. Geoenviron. Eng., in press.
Yuceman, M. S., Tang, W. H., and Ang, A. H. S. (1973). “A probabilistic study of safety and design of earth slopes.” Civil engineering studies, Structural Research Series 402, University of Illinois Press, Urbana, Ill.
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© 2008 ASCE.
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Received: Dec 12, 2006
Accepted: Jul 13, 2007
Published online: Mar 1, 2008
Published in print: Mar 2008
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