Seismic Behavior of Building Frames Considering Dynamic Soil-Structure Interaction

Abstract

The seismic excitation experienced by structures is a function of the earthquake source, travel path effects, local site effects, and soil-structure interaction (SSI) influences. The result of the first three of these factors is referred to as free-field ground motion. The structural response to free-field motion is influenced by the SSI. In particular, accelerations within structures are affected by the flexibility of the foundation support and variations between the foundation and free-field motions. Consequently, an accurate assessment of inertial forces and displacements in structures can require a rational treatment of SSI effects. In the current study, to depict these effects on the seismic response of moment-resisting building frames, a 10-story moment-resisting building frame resting on a shallow foundation was selected in conjunction with three soil types with shear-wave velocities of less than 600 m/s, representing Soil Classes Ce, De, and Ee according to an existing Australian Standard. The structural sections were designed after applying dynamic nonlinear time-history analysis, based on both the elastic method, and inelastic procedure using the elastic-perfectly plastic behavior of the structural elements. The frame sections were modeled and analyzed using the finite-difference method andthe