“…Poulos (1971b) (Poulos 1975, Banerjee 1978, Banerjee and Davies 1980, Sharnouby and Novak 1985, Basile 1999, Xu and Poulos 2000. The finite element method, with several modifications (e.g., finite elements with Fourier technique, finite elements with substructuring, finite elements with periodic boundary conditions), has also been used quite extensively to model pile groups in elastic and elastoplastic soils (Chow 1987, Shibata et al 1988, Kooijman 1989, Brown and Shie 1991, Bransby 1996, Zhang et al 1999b, Wakai et al 1999, Zhang and Small 2000, Law and Lam 2001, Budiman and Ahn 2005. That apart, the discrete element method (Holloway et al 1981), the finite difference method (Comodromos and Pitilakis 2005) and the variational method (Shen and Teh 2002) have been used to analyze pile groups.…”