MODELING FLUID SATURATION EFFECTS ON SEISMIC AMPLIFICATION
Local conditions of geological settings and soils influence seismic waves as they pass through the system. These conditions can significantly alter the amplitude, frequencies, and duration of the seismic waves, affecting the intensity of ground shaking experienced during an earthquake. The fluid saturation can play a significant role in modifying this site’s effects. However, its understanding has not been fully explored because it is commonly believed that the fluid effects are constrained to P-waves, which are not critical in site characterization. Nevertheless, the S-waves are not free of fluid effects in the complex system that a saturated medium represents. In this work, we analyze how the saturation of a soil layer affects the response to S-waves coming from the earth’s interior. We perform a semi-analytical analysis of this case by representing the soil as a porous layer and modeling its response using the theory of poroelasticity. This analysis shows that saturation can affect the layer’s response even to incident S-waves, highlighting the importance of accounting for saturation in seismic hazard assessments. This work was supported by DGPA-UNAM Postdoctoral Program (POSDOC) and PAPIIT Project IN105523.