ANALYSIS OF GROUND MOTION AMPLIFICATION OF SEDIMENTARY BASINS: STUDY ON THE HEAVILY DAMAGED BELT ZONE DURING 1995 KOBE EARTHQUAKE

摘要

A direct three-dimensional (3-D) as well as 2.5-dimensional (2.5-D) boundary element method is applied to evaluate seismic responses in 3-D and 2-D sedimentary basin to estimate the amplification characteristics of the ground motions in the heavily damaged belt zone in Kobe City during the 1995 Hyogo-ken earthquake. We have utilized the Green's functions for an elastic half-space medium to formulate boundary integral equations in terms of displacements and tractions at the medium interface in both 3-D and 2.5-D BEM. We examined in details the effects of different types of incident waves such as plane waves, a single point source, and a moving fault model on the responses of 3-D sedimentary basin and the effects of different types of cross-section of the 2-D sedimentary basin on the spatial variation of ground motions in the 2-D basin taking into account effects of 3-D fault sources.