A Seismic Model for the Periodic Pile‐Plate Road Foundation Based on the P2.5D Finite Element Method

ABSTRACT Pile‐plate road foundation (PRF) is a new type of road foundation arising in recent years. As the seismic wave is an important kind of dynamic loads, the dynamic analysis of the PRF under seismic wave is thus necessary for its dynamic design. To simplify the analysis of the PRF under seismic waves, the PRF is simplified as the periodic pile‐plate road foundation (PPRF) in this study. To establish the dynamic model for this PPRF, the PPRF is divided into two regions first, namely, the regions I and II. Region I is the region of interest of the PPRF, containing the bedrock, soil layers, embankment, pile rows, and plate, while the region II is the surrounding domain for the region I, including the soil layers and bedrock. In this study, the region I is treated by the periodic 2.5D finite element method (P2.5D FEM) and corresponding P2.5D FEM equations are obtained. For the region II, the periodic thin layer method (PTLM) is established and is used to establish the traction‐displacement relation at the regions I–II interface. With the obtained traction‐displacement relation, the transmitting boundary condition is imposed on the region I, and the incident seismic wave is input to the region I, yielding the P2.5D FE‐TLM model for the PPRF. Based on the established P2.5D FE‐TLM model, some results for the response of the PPRF to the incident surface waves are presented.