Simulation of the spatially correlated multiple-station earthquake ground motions of the coupled alluvial valley-hill terrain

Abstract

Based on both the boundary element and spectral representation methods, an effective simulation method for multiple-station spatially correlated ground motions on both bedrock and surface is developed, incorporating the spectral density function, coherence function, and site transfer function that consider the wave scattering effect. The accuracy and feasibility of the present method is validated by a typical numerical example. Our results indicate that at the coupled alluvial valley-hill terrain, the presence of the mountain enlarges the ground motion of the alluvial valley significantly; the existence of alluvial valley enlarges the ground motion at the ridge of the mountain to some extent and weakens the ground motion at the top of the mountain. The local site conditions significantly affect the multipoint spatially correlated earthquake ground motions. It is necessary to use spatially varying ground motions with the rational consideration of local site effects as input during the seismic analysis of long-span structures