Evaluation of Dynamic Earth Pressure Acting on Building Basement Walls in Liquefiable Soil Using 1 g Shaking Table Tests

This is the authors' abstract. We don't add key points for this paper.

Accurate estimation of dynamic earth pressure on basement walls in liquefiable soil is essential for seismic safety, yet remains challenging because of complex soil–structure interaction. This study proposes a practical method for estimating dynamic earth pressure under liquefaction conditions by decomposing the dynamic thrust into non-fluctuating and fluctuating components, each primarily governed by the free-field excess pore water pressure ratio and the basement base acceleration. Six 1 g shaking table tests were conducted on model buildings with three different heights and two basement support conditions (fixed and embedded) to examine the seismic performance of free-field soil, buildings, and basement walls. Free-field soil displacement was initially aligned with basement floor displacement during early shaking but decreased significantly once liquefaction developed. Dynamic thrust was consistently out of phase with basement displacement and increased markedly under liquefied backfill compared with dry backfill. Under liquefaction, the pressure distribution consistently exhibited a triangular shape regardless of building height or basement condition. The proposed method reasonably estimated dynamic thrust in liquefied soil, outperforming conventional approaches and reducing estimation errors. These findings provide a practical framework for evaluating dynamic earth pressure in liquefiable soils, contributing to safer and more rational seismic design of basement structures.