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Analysis of the piled raft for three load patterns: A parametric study

  • Chore, H.S. (Department of Civil Engineering, Datta Meghe College of Engineering) ;
  • Siddiqui, M.J. (Department of Civil Engineering, Anjuman- E- Islam A.R. Kalsekar Polytechnic)
  • Received : 2013.11.04
  • Accepted : 2014.01.24
  • Published : 2013.09.25

Abstract

The piled raft is a geotechnical construction, consisting of the three elements-piles, raft and the soil, that is applied for the foundation of a tall buildings in an increasing number. The piled rafts nowadays are preferred as the foundation to reduce the overall and differential settlements; and also, provides an economical foundation option for circumstances where the performance of the raft alone does not satisfy the design requirements. The finite element analysis of the piled raft foundation is presented in this paper. The numerical procedure is programmed into finite element based software SAFE in order to conduct the parametric study wherein soil modulus and raft thickness is varied for constant pile diameter. The problems of piled raft for three different load patterns as considered in the available literature (Sawant et al. 2012) are analyzed here using SAFE. The results obtained for load pattern-I using SAFE are compared with those obtained by Sawant et al. (2012). The fair agreement is observed in the results which demonstrate the accuracy of the procedure employed in the present investigation. Further, substantial reduction in maximum deflections and moments are found in piled raft as compared to that in raft. The reduction in deflections is observed with increase in raft thickness and soil modulus. The decrease in maximum moments with increase in soil modulus is seen in raft whereas increase in maximum moments is seen in piled raft. The raft thickness and soil modulus affects the response of the type of the foundation considered in the present investigation.

Keywords

References

  1. Baziar, M.H., Ghorbani, A. and Katzenbach, R. (2009), "Small-scale model test and three dimensional analysis of piled -raft foundation on medium-dense sand", Int. J. Civil. Eng., 7(3), 170-175.
  2. Brown, P.T. and Wiesner, T.J. (1975), "The behaviour of uniformly loaded piled strip footings", Soils Found., 15(4), 13-21.
  3. Butterfield, R. and Banerjee, P.K. (1971), "The problem of pile group - pile cap interaction", Geotechnique, 21(2), 135-142. https://doi.org/10.1680/geot.1971.21.2.135
  4. Chen, K.S., Karasudhi, P. and Lee, S.L. (1974), "Force at a point in the interior of layered elastic half-space", Int. J. Solids Struct., 10(11), 1179-1199. https://doi.org/10.1016/0020-7683(74)90067-5
  5. Cheng, Z. (2011), "Prediction and measurement of settlement of a piled raft foundation over thick soft ground", Electron. J. Geotech. Eng. (EJGE), 16(A), 125-136.
  6. Chow, Y.K. (1987), "Axial and lateral response of pile groups embedded in non-homogeneous soil", Int. J. Numer. Anal. Meth., 11(6), 621-638. https://doi.org/10.1002/nag.1610110607
  7. Chow, Y.K. and Teh, C.I. (1991), "Pile-cap-pile-group interaction in non- homogeneous soil", J. Geotech. Geoenviron., 117(11), 1655-1667.
  8. Chow, Y.K., Poulos, H.G. and Small, J.C. (2011), "Piled raft foundations for tall buildings", Geotech. Eng. J. (South East Asian Geotechnical Society), 42(2), 78-84.
  9. Clancy, P. and Randolph, M.F. (1993), "An approximate analysis procedure for piled raft foundations", Int. J. Numer. Anal. Met., 17(12), 849-869. https://doi.org/10.1002/nag.1610171203
  10. Franke, E., El-Mossallamy, Y. and Wittmann, P. (2000), Design Applications of Raft Foundation, Thomas Telford, London, UK.
  11. Gandhi, S.R. and Maharaj, D.K. (1996), "Analysis of piled raft foundation", Proceedings of the 6th International Conference on Piling and Deep Foundations, Bombay, India, January.
  12. Hain, S.J. and Lee, I.K. (1978), "The Analysis of flexible raft-pile systems", Geotechnique, 28(1), 65-83. https://doi.org/10.1680/geot.1978.28.1.65
  13. Hooper, J.A. (1973), "Observations on the behaviour of a piled-raft foundation on London Clay", Proceedings of the Institution of Civil Engineers - Part 2, 55(4), 855-877. https://doi.org/10.1680/iicep.1973.4144
  14. Kakurai, M., Yamashita, K. and Tomono, M. (1987), "Settlement behaviour of piled raft foundation on soft ground", Proceedings of the 8th Asian Regional Conference on Soil Mechanics and Foundation Engineering, Kyoto, Japan.
  15. Katzenbach, R. and Reul, O. (1997), "Design and performance of piled rafts", Proceedings of the 14th International Conference on Soil Mechanics and Foundation Engineering, Hamburg, Germany.
  16. Katzenbach, R., Arslan, U. and Moormann, C. (2000), Design Applications of Raft Foundation, Thomas Telford, London, UK.
  17. Kitiyodom, P. and Matsumoto, T. (2003), "A simplified analysis method for piled raft foundations in non-homogeneous soils", Int. J. Numer. Anal. Met., 27(2), 88-109.
  18. Kuwabara, F. (1989), "An elastic analysis for piled raft foundations in a homogeneous soil", Soils Found., 29(1), 82-92. https://doi.org/10.3208/sandf1972.29.82
  19. Liu, W. and Novak, M. (1991), "Soil-pile-cap static interaction analysis by finite and infinite elements", Can. Geotech. J., 28(6), 771-783 https://doi.org/10.1139/t91-094
  20. Liang, F.Y. and Chen, L.Z. (2004), "A modified variation approach for the analysis of piled raft foundation", Mech. Res. Commun., 31, 593-604. https://doi.org/10.1016/j.mechrescom.2004.03.003
  21. Madhav, M.R. and Karmarkar, R.S. (1982), "Elasto-plastic settlement of rigid footings", J. Geotech. Eng. Div. (ASCE), 108(GT-3), 483-488.
  22. Maharaj, D.K. and Gandhi, S.R. (2004), "Non-linear finite element analysis of piled raft foundations", Proceedings of the ICE - Geotech. Eng., 157(3), 107-113. https://doi.org/10.1680/geng.2004.157.3.107
  23. Mendonca, A.V. and De Paiva, J.B. (2003), "A Boundary element method for the static analysis of raft foundations on piles", Eng. Anal. Bound. Elem., 24(3), 237-247.
  24. Noh, E.Y., Huang, M., Surarak, C., Adamec, R. and Balasurbamaniam, A.S. (2008), "Finite element modeling for piled-raft in sand", Proceedings of the 11th East Asia-Pacific Conference on Structural, Engineering and Construction (EASEC-11), Taipei, Taiwan.
  25. Ottaviani, M. (1975), "Three-dimensional finite element analysis of vertically loaded pile groups", Geotechnique, 25(2), 159-174. https://doi.org/10.1680/geot.1975.25.2.159
  26. Poulos, H.G. (1994), "An approximate numerical analysis of piled raft interaction", Int. J. Numer. Anal. Met., 18(2), 73-92. https://doi.org/10.1002/nag.1610180202
  27. Poulos, H.G., Badelow, F., Small, J.C. and Moyes, P. (2006), "Economic foundation design for tall buildings", Proceedings of the 10th International Conference on Piling and Deep Foundations, Amsterdam, Netherlands.
  28. Prakoso, W.A. and Kulhawy, F.H. (2001), "Contribution to piled raft foundation design" J. Geotech. Geoenviron., 127(1), 17-24. https://doi.org/10.1061/(ASCE)1090-0241(2001)127:1(17)
  29. Randolph, M.F. (1983), "Design of piled raft foundations", Proceedings of the International Symposium on Recent Developments in Laboratory and Field Tests and Analysis of Geotechnical Problems, Bangkok, Thailand.
  30. Reul, O. and Randolph, M.F. (2003), "Piled rafts in over consolidated clay: comparison of in-situ measurements and numerical analyses", Geotechnique, 53(3), 301-315. https://doi.org/10.1680/geot.2003.53.3.301
  31. Sales, M.M., Small, J.C. and Poulos, H.G. (2010), "Compensated piled rafts in clayey soils: behaviour, measurements, and predictions", Can. Geotech. J., 47(3), 327-345. https://doi.org/10.1139/T09-106
  32. Sawant, V.A., Ladhane, K. and Pawar, S. (2012), "Parametric study of piled raft for three load-patterns", Coupled System Mech., Int. J., 1(2), 115-131. https://doi.org/10.12989/csm.2012.1.2.115
  33. Shen, W.Y., Chow, Y.K. and Yong, K.Y. (1999), "Variational solution for vertically loaded pile groups in an elastic half-space", Geotechnique, 49(2), 199-213. https://doi.org/10.1680/geot.1999.49.2.199
  34. Shen, W.Y. and Teh, C.I. (2002), "Analysis of laterally loaded pile groups using a variational approach", Geotechnique, 52(3), 201-208. https://doi.org/10.1680/geot.2002.52.3.201
  35. Sinha, J. (1997), "Piled raft foundations subjected to swelling and shrinking soils", Ph.D. Thesis (Unpublished), University of Sydney, Australia.
  36. Small, J.C. and Booker, J.R. (1984), "Finite layer analysis of layered elastic materials using flexibility approach, Part I. - Strip Loadings", Int. J. Numer. Anal, Met., 20, 1025-1037 https://doi.org/10.1002/nme.1620200606
  37. Small, J.C. and Booker, J.R. (1986), "Finite layer analysis of layered elastic materials using flexibility approach, Part II. - Circular and rectangular loadings", Int. J. Numer. Anal. Met., 23(5), 959-978. https://doi.org/10.1002/nme.1620230515
  38. Smith, I. M. and Wang, A. (1998), "Analysis of piled rafts", Int. J. Numer. Anal. Met., 22(10), 777-790. https://doi.org/10.1002/(SICI)1096-9853(1998100)22:10<777::AID-NAG940>3.0.CO;2-U
  39. Tan, Y.C., Chow, C.M. and Gue, S.S. (2005), "Piled raft with different pile length for medium rise buildings ob very soft clay", Proceedings of the 16th Int. Conf. Soil Mech. And Geot. Eng. (ICSMGE), Osaka, Japan, September.
  40. Thoiba Singh, N. and Baleshwar Singh (2008), "Interaction analysis for piled rafts in cohesive soils", Proceedings of the 12th International Conference on International Association for Computer Methods and Advances in Geomechanics (IACMAG), Goa, India.
  41. Wiesner, T.J. (1991). "Various applications of piled raft analysis", Proceedings of the International Conference on International Association for Computer Methods and Advances in Geomech., (Ed.:Beer, Booker and Carter), Balkema, Rotterdam.
  42. Xie X., Shou M. and Huang J. (2012), "Application study of long-short-piled raft foundation", Appl. Mech. Mater., 70, 242-245.

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