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Abstract: To evaluate the responses of fixed and pinned pile groups under torsion, a method is presented to analyze the nonlinear behavior of free-standing pile groups with rigid pile caps. The method is capable of simulating the nonlinear soil response in the near field using p-y and τ-θ curves, the far-field interactions through Mindlin’s and Randolph’s elastic solutions, and the coupling effect of lateral resistance on torsional resistance of the individual piles using an empirical factor. Based on comparisons of the solutions for fixed- and pinned-head, 1×2, 2×2, and 3×3 pile groups subjected to torsion, it was found that pile-cap connection significantly influences the torsional capacity of pile groups and the assignment of applied torques in the pile groups. In this study, the applied torques for the pinned-head pile groups are only 44%~64% of those for the corresponding fixed-head pile groups at a twist angle of 2°. Such a difference is mainly due to the change of the lateral resistances of individual piles in the groups.

[1] Budhu, M., 2000. Soil Mechanics and Foundations. John Wiley & Sons, New York.

[2] Chow, Y.K., 1985. Torsional response of piles in nonhomogeneous soil. Journal of Geotechnical Engineering, ASCE, 111(7):942-947.

[3] Guo, W.D., Randolph, M.F., 1996. Torsional piles in non-homogenous media. Computers and Geotechnics, 19(4):265-287.

[4] Hu, Z., McVay, M.C., Bloomquist, D., Herrera, R., Lai, P., 2006. Influence of torque on lateral capacity of drilled shafts in sands. Journal of Geotechnical and Geoenvironmental Engineering, ASCE, 132(4):456-464.

[5] Kong, L.G., 2006. Behavior of Pile Groups Subjected to Torsion. Ph.D Thesis, The Hong Kong University of Science and Technology, Hong Kong, China.

[6] Kong, L.G., Zhang, L.M., 2007a. Rate-controlled lateral-load pile tests using a robotic manipulator in centrifuge. Geotechnical Testing Journal, ASTM, 30(3):192-201.

[7] Kong, L.G., Zhang, L.M., 2007b. Centrifuge modeling of torsionally loaded pile groups. Journal of Geotechnical and Geoenvironmental Engineering, ASCE, 133(11):1374-1384.

[8] Laue, J., Sonntag, T., 1998. Pile Subjected to Torsion. Proceedings of Centrifuge ’98, 1:187-192.

[9] Leung, C.F., Chow, Y.K., 1987. Response of pile groups subjected to lateral loads. International Journal for Numerical and Analytical Methods in Geomechanics, 11(3):307-314.

[10] Mindlin, R.D., 1936. Force at a point in the interior of a semi-infinite solid. Physics, 7(5):195-202.

[11] Poulos, H.G., 1971. Behaviour of laterally loaded piles: II—pile groups. Journal of Soil Mechanics and Foundation Division, ASCE, 97(SM5):733-751.

[12] Poulos, H.G., 1975. Torsional response of piles. Journal of Geotechnical Engineering Division, ASCE, 101:1019-1035.

[13] Randolph, M.F., 1981. The response of flexible piles to lateral loading. Géotechnique, 31(2):247-259.

[14] Zhang, L.M., Tsang, C.Y.M., 2005. Three-dimensional Analysis of Torsionally Loaded Large-diameter Bored Pile Groups. Proceedings of the 6th International Conference on Tall Buildings, 6-8 December 2005. World Scientific, New Jersey, p.311-317.

[15] Zhang, L.M., Kong, L.G., 2006. Centrifuge modeling of torsional response of piles in sand. Canadian Geotechnical Journal, 43(5):500-515.