Three-dimensional modeling of arbitrarily oblique incidence of P and SV waves in time domain for local site effect problems
摘要
This manuscript presents a numerical framework for three-dimensional modeling of arbitrarily oblique incidence of P and SV waves through multilayered soil in time domain for local site effect problems, including soil-structure interaction. The framework consists of two main stages: (i) obtaining the free-field displacement histories at some preselected locations of the layered soil subjected to obliquely incident P-SV waves, using Fourier transform and Stiffness Matrix Method, and (ii) calculating the effective forces acting at these locations by means of Domain Reduction Method, and conducting the finite element analysis in time domain. Results of the proposed framework show good agreements with published studies for a variety of soil profiles, with and without topographical features, in both two- and three-dimensional configurations. Subsequently, the framework was used to analyze a 12-story building rested on a layered soil medium in the scenario of Kobe earthquake. To demonstrate the capability of the proposed framework in dealing with nonlinearity, a soil block underneath the foundation was simulated using a nonlinear hysteresis material model. This example highlights the significant effect of the azimuth angle of seismic waves traveling in three-dimensional spaces on the peak acceleration, peak inter-story drift ratio, and foundation rocking of the building.