Calculation of Earthquake Effective Input Motion to the Soilstructure System for Coupled Rigorous-Substructure SSI Analysis

In this study, records of some earthquakes have been used in order to find the effective input motion to the soil-structure system for the sake of seismic soil-structure interaction (SSI) analysis. The motion replaces the freefield earthquake record and manifests the real motion input from the far-field to the near- and far-field interface which serves as the truncation limit. To satisfy the boundary condition the Scaled Boundary Finite Element Method (SBFEM) istaken. The media is inspected assuming different material conditions including compressible and incompressible cases and outputs are compared revealing differences caused by changes in the material compressibility and soil type. The analyses are carried out for infinite halfspace consisting of sand and clay. It is observed that the effective input motion is primarily smaller than the freefield motion for acceleration, velocity and displacement time histories and that the clayey field causes more damping to the deconvolved motion which means it can result in more amplification from depth to surface

Keywords:

Soil-structure interaction , earthquake , scaled boundary FEM , effective input motion , compressible and incompressible conditions