Numerical Simulation of Seismic Response of a Cantilevered Sheet-Pile Wall with Liquefiable Backfill Sand

Abstract

This paper presents numerical predictions for a dynamic centrifuge test of a submerged cantilevered sheet-pile wall retaining a liquefiable backfill. The numerical analysis was performed using PM4sand model in FLAC2D. The PM4sand model was calibrated for a liquefaction strength based on cyclic torsional shear tests, while the modulus reduction at larger shear strains (gamma > 1%) was calibrated based on an empirical G/G(max) curve. The wall rotation was driven by shear failure in the backfill due to excess pore pressure buildup. The use of relative density (D-r) estimated from measured cone penetration resistance over D-r from mass and volume measurements resulted in a better prediction of liquefaction triggering and wall rotation. There was a further improvement in the predicted wall rotation when the degradation of elastic shear modulus at large shear strains fitted the empirical curve. However, the post-liquefaction backfill settlement could not be predicted accurately due to limitation of the PM4sand model.