Effect of principal stress rotation on the wave-induced seabed response around a submerged breakwater

Abstract

Principal stress rotation (PSR) is one of the main features for the stress condition in the soil element underneath a structure subject to cyclic waves. This paper aims to present an integrated numerical model to investigate the influence of principal stress rotation (PSR) on the wave-induced soil response around a submerged rubble mound breakwater. In the developed model, the VARANS equation is used for governing the flow motion inside and outside the porous media; Biot’s dynamic equation is used for linking the soil skeleton and pore fluid interaction; the modified PZIII model considering the impact of PSR is used to reproduce the foundation behavior under cyclic shearing. Numerical results indicate that ignoring the PSR involved in the wave-seabed–structure interactions (WSSI) will significantly underestimate the cumulative shear strains in seafloor and subsequent build-up of pore water pressure, especially in the region underneath the breakwater.