Analytical Solution of Seismic Scattering on Sea Slope Induced by P1 Wave

Drawing upon the theoretical frameworks of ideal fluid wave theory and Biot saturated porous media wave theory, a dynamic interaction model is established for seawater-seabed on saturated porous soil slopes. The analytical solution of the seismic scattering response of slope sea floor under the incident plane P1 wave is derived by using the oblique coordinate -Hankel function integral method. Then, based on the obtained analytical solution of frequency-domain scattering, the multi-point ground motion of the site is simulated, which solves the gap of the theoretical scheme related to the irregular seabed topography. This program also lays the foundation for seismic differential simulation of slope seabed under P1 wave incidents. Further analysis of the model explores the sensitivity of parameters such as incidence angle, seawater depth, and incidence frequency. The results indicate a decrease in the vertical component of seismic motion with increasing sea layer depth, while the horizontal component remains relatively stable. Notably, the local seabed of saturated slopes exhibits a pronounced amplification effect in response to seismic motion. Moreover, incident frequency emerges as a crucial factor influencing submarine ground motion, with higher frequencies correlating to greater seismic responses. Consequently, relying on seismic data from land or flat terrain for studying the dynamic response of seabed under the influence of uneven terrain may yield inaccurate results.