New Geometric Average Method for Calculation of Ultimate Bearing Capacity of Shallow Foundations on Stratified Sands
Publication: International Journal of Geomechanics
Volume 13, Issue 2
Abstract
Obtaining the bearing capacity of shallow foundations in a nonhomogeneous soil profile has been a challenging task in geotechnical engineering. In this paper, a new geometric average for the equivalent soil friction angle () of various layers beneath shallow strip foundations is used to determine the ultimate bearing capacity. This approach is based on the concept of geometric mean value; however, the method involves applying a power to each variable, which is here the internal friction angle of each soil layer. Numerical methods based on finite elements and also experimental data have been used to verify the presented average method. It will be shown that data obtained from the developed method are well in agreement with those obtained from finite-element analysis and with those obtained from full-scale loading. This agreement is closer when the difference between the shear strength parameters of layers is small, which is the case for sedimentary soil profiles and also for artificially compacted soils. A computer program has been developed to investigate the influence of various parameters and to compute equivalent for different cases.
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References
Bouassida, M., Jellali, B., and Porbaha, A. (2009). “Limit analysis of rigid foundations on floating columns.” Int. J. Geomech., 9(3), 89–101.
Bowles, J. E. (1996). Foundation analysis and design, 5th Ed., McGraw Hill, New York.
Burd, H. J., and Frydman, S. (1997). “Bearing capacity of plane-strain footings on layered soils.” Can. Geotech. J., 34(2), 241–253.
Das, B. M. (1997). Advanced soil mechanics, 2nd Ed., Taylor and Francis, Washington, DC.
De Beer, E. E. (1970). “Experimental determination of the shape factors of sand. Geotechnique, 20(4), 387–411.
Dewaikar, D. M., and Mohapatra, B. G. (2003). “Computation of bearing capacity factor Nγ-Prandtl’s mechanism.” Soils Found., 43(3), 1–10.
Eslami, A., and Gholami, M. (2003). “Bearing capacity analysis of shallow foundations from CPT data.” Res. J. Eng., Amirkabir Univ. Technol., 56(B), 1166–1184 (in Persian).
FLAC [Computer software]. Minneapolis, Itasca.
Florkiewicz, A. (1989). “Upper bound to bearing capacity of layered soils.” Can. Geotech. J., 26(4), 730–736.
Frydman, S., and Burd, H. J. (1997). “Numerical studies of bearing capacity factor Nγ.” J. Geotech. Geoenviron. Eng., 123(1), 20–29.
Gibbens, R., and Briaud, J. L. (1994). “Data and prediction request for the spread footing prediction event.” Predicted and measured behavior of five spread footings on sand, ASCE, Reston, VA, 11–85.
Griffiths, D. V. (1982). “Computation of bearing capacity factors using finite elements.” Geotechnique, 32(3), 195–202.
Hansen, J. B. (1970). “A revised and extended formula for bearing capacity.” Bulletin No. 28, Danish Geotechnical Institute, Copenhagen, Denmark.
Kumar, J., and Khatri, V. N. (2008). “Effect of footing roughness on lower bound Nγ values.” Int. J. Geomech., 8(3), 176–187.
Manoharan, N., and Dasgupta, S. P. (1995). “Bearing capacity of surface footings by finite elements.” Comp. Struct., 54(4), 563–586.
Mayerhoff, G. G. (1951). “The ultimate bearing capacity of foundations.” Geotechnique, 2(4), 301–331.
Michalowski, R. L., and Shi, L. (1995). “Bearing capacity of footings over two-layer foundation soils.” J. Geotech. Engrg., 121(5), 421–428.
Okamura, M., Mihara, A., Takemura, J., and Kuwano, J. (2002). “Effect of footing size and aspect ratio on the bearing capacity of sand subjected to eccentric loading.” Soils Found., 42(4), 43–56.
OXFEM [Computer software]. Oxford, United Kingdom, Univ. of Oxford.
Plaxis 7.20 [Computer software]. Delft, Netherlands, Plaxis.
Rayhani, M. H. T., and El Naggar, M. H. (2008). “Numerical modeling of seismic response of rigid foundation on soft soil.” Int. J. Geomech., 8(6), 336–346.
Schanz, T., and Vermeer, P. A. (1996). “Angles of friction and dilatancy of sand.” Geotechnique, 46(1), 145–151.
Singh, S., Sivakugan, N., and Shukla, S. K. (2010). “Can soil arching be insensitive to ϕ?” Int. J. Geomech., 10(3), 124–128.
Terzaghi, K. (1943). Theoretical soil mechanics, Wiley, New York.
Vesic, A. S. (1973). “Analysis of ultimate loads of shallow foundation.” J. Soil Mech. Found. Div., 99(1), 45–73.
Woodward, P. K., Nesnas, K., and Griffiths, D. V. (2000). “Advanced numerical modeling of footings on granular soils.” Numerical methods in geotechnical engineering, ASCE, Reston, VA, 88–101.
Yang, X.-L., Li, L., and Yin, J.-H. (2004). “Seismic and static stability analysis for rock slopes by a kinematical approach.” Geotechnique, 54(8), 543–549.
Yang, X.-L., and Yin, J.-H. (2005). “Upper bound solution for ultimate bearing capacity with a modified Hoek-Brown failure criterion.” Int. J. Rock Min. Sci., 42(4), 550–560.
Yin, J.-H., Wang, Y. J., and Selvadurai, A. P. S. (2001). “The influence of a non-associative flow rule on the calculation of bearing capacity of a strip footing.” J. Geotech. Geoenviron. Eng., 127(11), 985–989.
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Information
Published In
International Journal of Geomechanics
Volume 13 • Issue 2 • April 2013
Pages: 101 - 108
Copyright
© 2013 American Society of Civil Engineers.
History
Received: Oct 26, 2010
Accepted: Oct 14, 2011
Published online: Oct 18, 2011
Published in print: Apr 1, 2013
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