Simulation of Near-Fault Strong-Ground Motion Using Hybrid Green's Functions

Abstract

The recently proposed hybrid Green's function method is designed to combine the advantages of both deterministic and stochastic approaches to simulating broadband ground motion when records of small events are not available. The method has the flexibility of incorporating complexities in the source, wave path, and local- site effects into strong ground motion simulations. In this article we analyze its effectiveness at simulating near-fault ground motions by comparisons with the em- pirical source time function method, empirical ground-motion-attenuation relations, and recorded near-fault ground motion. We present a simple model for introducing the effect of the radiation pattern to the stochastic Green's functions in the inter- mediate frequency range (1-3 Hz). The numerical test results of the method and the generally good agreement between simulated and recorded ground motion from the 17 January 1995 Kobe earthquake shown in this study indicate that the technique has the capability of reproducing the main characteristics of near-fault ground mo- tion.