A review of seismic soil-pile-superstructure interaction methods

The role of the Seismic-Soil–Pile–Superstructure Interaction (SSPSI) is usually assumed negligible for structural design purposes. This is mainly to avoid the complex task of computing the inertial and kinematic interactions for superstructure- pile and soil-pile systems respectively. The results obtained from recent earthquakes demonstrate that considering a fixed-base structure could be misleading, and neglecting the effects of SSPSI could lead to risky designs mainly for mid-rise and high-rise buildings founded on soft soils. The SSPSI behavior is predominantly nonlinear and this makes it complicated. The field observations of pile failures after seismic events have highlighted the importance of incorporating kinematic effects in the design process. Hence, some codes states those kinematic effects should be considered during the pile design process. In a soil-pile-superstructure system, the seismic load is resisted by the interaction effects between pile, soil and superstructures, which in turn depend on soil, pile and superstructure materials and geometry, slenderness ratio in pile, pile type (vertical or inclined), loading type and its specifications. The difficulty in the accountability of the influencing factors necessitates a detailed investigation on SSPSI. Reviewing the existing literature reveals that studies on SSPSI effects have been generally carried out in two different directions: investigation methods and types of pile foundation. As a result, a SSPSI detailed literature review is presented in this paper.