Numerical study for dynamic response of marine sediments subjected to underwater explosion

This paper developed a three-dimensional numerical model for saturated soil response induced by underwater explosion in marine environment. Unlike previous studies, three new features are included in the present model: (1) genuine detonation with real explosive materials; (2) coupled ALE (Arbitrary-Lagrangian-Eulerian)-Lagrangian algorithm for large seabed deformation; and (3) u-p formulation considering pore water pressure effect. The proposed explosion model is validated against experiment data available in the literature. Several parametric studies are carried out to investigate seabed response considering various soil types and TNT equivalent. Time series of total stress and pore pressure from sandy bed and clayey bed subjected to explosive loads are presented. Special attention is given to the distribution of peak total stress and pore pressure during propagation of blast wave. To facilitate engineering practice, a series of formulas for evaluating attenuation of peak total stress and pore water pressure are proposed.