A STUDY ON THE GROUND MOTION CHARACTERISTICS OF TAIPEI BASIN, TAIWAN, BASED ON OBSERVED STRONG MOTIONS AND MEASURED MICROTREMORS

摘要

Taipei basin suffered serious damage on building structures during the 1999 Chi-Chi earthquake, even though it was located 100 km away from the epicenter. The purpose of this paper is to discuss the relationship between the damage occurred and the ground motion characteristics observed in the Taipei basin and to draw a seismic microzoning map for the region by taking into account the analyzed results about the earthquake motions,microtremors and the damage distribution. For more discussion about site effect evaluation, observed strong motions of two earthquakes, which happened in 1994, 1995 will be used in addition to the 1999 earthquake.Such records of strong motions of those earthquakes were offered by the Central Weather Bureau (CWB),Taiwan. Measurements of microtremors inside Taipei basin were made in 2000 after the Chi-Chi earthquake.