Effects of Principal Stress Rotation on the Fluid-Induced Soil Response in a Porous Seabed

Abstract

Principal stress rotation (PSR) is an important feature for describing the stress status of marine sediments subject to cyclic loading. In this study, a one-way coupled numerical model that combines the fluid model (for wave–current interactions) and the soil model (including the effect of PSR) was established. Then, the proposed model was incorporated into the finite element analysis procedure DIANA-SWANDYNE II with PSR effects incorporated and further validated by the experimental data available in the literature. Finally, the impact of PSR on the pore-water pressures and the resultant seabed liquefaction were investigated using the numerical model, and it was found that PSR had a significant influence on the seabed response to combined wave and current loading.

Response of a Porous Seabed around an Immersed Tunnel under Wave Loading: Meshfree Model

“…It can be seen that the result obtained from both the wave model and seabed model are in good agreement with the test data, which indicate that the present model is capable for simulating the wave motion in the fluid domain as well as the corresponding soil response of a sandy seabed. The present model Laboratory experiments [38] (a) Water surface elevation (η) The present model PZIII results [52] Laboratory experiments [38] (b) Wave-induced pore pressure in seabed (p s ) The second validation in this section is to compare with the previous laboratory experiments conducted by Qi and Gao [38]. Unlike the previous case, this test simulates the seabed dynamic response under wave and current, which are generated synchronously.…”

“…Thus, the current model performs well for simulating a more realistic marine dynamic elastic behaviour including both the fluid and soil parts. The present model Laboratory experiments [52] (a) Water surface elevation (η) The present model PZIII results [52] Laboratory experiments [38] (b) Wave-induced pore pressure in seabed (p s )…”

“…However, it is quite limited in terms of the experimental data available for the case of immersed tunnel. Thus, the verifications of the integration model are carried out by comparison with the laboratory experiments and the FEM (Finite Element Method) results from DIANA-SWANDYNE II [52] for the seabed without the structure instead in this section. Qi and Gao [38] conducted a series of flume tests considering wave and wave combined currents as dynamic loading, respectively.…”

“…Validation of the (a) Water surface elevation (η) and (b) Wave-induced pore pressure in seabed (p s ) under wave combined current loading at z = −0.1 m against the experimental data (which was from[38]) and FEM result (calculated from DIANA-SWANDYNE II[52]). …”

Coastal Geohazard and Offshore Geotechnics

“…In this Special Issue, eighteen papers were published, covering three main themes: (1) mechanism of fluid-seabed interactions and its associate seabed instability under dynamic loading [1][2][3][4][5];…”