Abstract: A lenticle existing in engineering site affacts significantly on the earthquake ground motion. There exists obvious difference between the seismic response of water-saturated poroelastic site and the corresponding dry site. However, there are few studies in literature on influence of lenticle on seismic response in deep water-saturated poroelastic soft site up to now. Using finite element and indirect boundary element coupled method (FEM-IBEM), this paper investigates the effect of width, thickness and embedded depth of a lenticle on dynamic structural response by the nonlinear dynamic saturated soil-structure interaction model, and particularly analyzes the effect of dynamic coupling effect between solid frame and pore water. The lenticle width, thickness and embedded depth show different effects on the structural response, resulting in obvious difference with those of a lenticle in dry site. The dynamic coupling effect between solid frame and pore water has significant effect on seismic response of the structure.

Key words: deep water-saturated poroelastic soft site, FEM-IBEM coupled method, lenticle, dynamic soil-structure interaction, seismic response, dynamic coupling effect between solid frame and pore water