Investigation of Seismic Response of S-Wave Incident Bedrock-Saturated Soil-Unsaturated Soil Site under Thermal Effect

Abstract

Based on the theory of elastic wave propagation under thermal effects, this study develops a bedrock-saturated soil-unsaturated soil site model under S-wave incidence to investigate its seismic dynamic response. The analytical solution is derived using Helmholtz decomposition with appropriate boundary conditions. Numerical simulations systematically examine how thermal conductivity, saturation, and ground water level affect ground motion characteristics. Results demonstrate significant differences in displacement amplification factors between thermal and isothermal models. The thermal expansion coefficient and kelvin medium temperature substantially influence vertical displacement amplification, whereas thermal conductivity and heat flux phase delay show minimal effects. With increasing incident angle, horizontal displacement amplification decreases progressively while vertical amplification first increases then decreases. Higher ground water levels and saturation reduce horizontal displacement amplification but enhance vertical amplification.