2016年台湾高雄地震场地效应及砂土液化破坏概述

Seismic damage summarization of site effect and soil liquefaction in 2016 Kaohsiung earthquake

2016年2月6日高雄发生了里氏6.7级地震,造成了基础设施和房屋建筑重大损失,本文对现有成果进行了初步分析和总结。结果表明:虽然地震发生在高雄市,但台南地区震害严重,其主要原因是场地效应和砂土液化的影响;台南地区所处的嘉南平原土层偏软、偏厚,地震后场址放大效应影响显著,增加了震度等级;嘉南平原是台湾最大的冲积平原,此次地震液化区域就集中在这一地区;液化不仅会造成显著震陷引起房屋破坏,而且可能引起长周期地震波放大效应加重结构振动破坏;此次地震震出了全台湾土壤液化危机,台湾地区不得不紧急出台液化潜势区划图,这对我国大陆地区液化区划技术的发展和应用是一个很好的警示。台南地区晃动时间由高雄震中1.74 s显著变长到8.16 s,专家分析认为是由于软土场地和土壤液化共同作用导致的,其具体现象和机理值得深入研究。

On 2 February,2016 an earthquake of magnitude 6. 7 occurs in Kaohsiung,which causes in a significant disaster of infrastructure and construction. This paper makes a preliminary analysis and summary of the existing results. Due to the influence of site effect and soil liquefaction,more serious damage take place in the Tainan area,and the shaking time is evident amplification from Kaohsiung＇s 1. 74 s to Tainan＇s 8. 16 s despite the epicenter in Kaohsiung. Tainan is located in the Chianan Plain which is Taiwan＇s largest alluvial plain,has soft and thick soil. After this earthquake,site amplification effect impacts on the Tainan area,increases intensity scale of this area,the liquefaction phenomena are concentrated in this plain. Not only soil liquefied causes significant seismic subsidence to destroy construction,but also it induces seismic wavelength periodic amplification effect that increase the structural vibration failure. This earthquake led to the soil liquefaction crisis in the Taiwan Island,which makes Taiwan administrations have to publish the map of liquefaction potential zone,and this is a warning for de-velopment and application of the Chinese mainland＇s liquefaction zoning technology. The mechanism of the phenomenon has a high value of scientific research about the longer shaking time by the influence of soil site and soil liquefaction.