Numerical simulation of wave-induced evolution of small-strain stiffness in submarine environments: Effects on seismic wave propagation

This paper aims to investigate the wave-induced evolution of small-strain stiffness and its effects on seismic wave propagation. To this end, an advanced numerical framework based on the dynamic porous media theory was developed, in which the Iwan multi-surface constitutive model was adopted to model the soil behavior during cyclic loading. Moreover, the numerical framework integrates key parameters such as ocean wave characteristics and depth-dependence seabed conditions to model the intricate interactions between waves and the seabed. Following model verification via analytical solutions and previous experimental data, comprehensive parameter studies are conducted, from which the effects of different wave conditions and seabed properties on the dynamic response of the seabed were obtained, revealing the wave-induced small- strain stiffness spatial and temporal variation. Subsequently, simulations of geophysical monitoring instants are conducted, assessing the impact of evolving small-strain stiffness on seismic wave propagation. The findings highlight the implications of stiffness changes on seismic wave propagation characteristics. The study provides valuable insights into the challenges and opportunities associated with interpreting geophysical data in dynamic submarine environments, offering implications for subsurface characterization and monitoring applications.