基于地形倾斜值的场地效应校正方法研究

Site conditions and amplification based on topographic slope

根据Wald等(2007)的研究发现,从地形数据里分离出来的倾斜值分布和用非单一来源得到的区域场地效应图有很好的相关性,但前者在质量和连续性方面又更胜一筹,且与实际观测所得到的速度分布较接近。本文阐述了以地形倾斜值求V3S0及做场地效应校正的原理和方法,据此方法从全球地形数据中得到研究区域的浅层剪切波速度V3S0分布图,并以2008年汶川地震为应用例子,求得场地放大因子,对初始地震动进行场地效应校正。

Site correction map derived from the slope of the topography is often well correlated with other independently-derived, regional-scale site-condition maps, but the latter maps vary in quality and continuity, and subsequently, also in their ability to match observed Vs30 measurements contained therein （Wald et al, 2007）. This method has good application in＇the USA, as well as in Taiwan, Italy, and Australia. This paper elaborates on the theory and the method of generating shear-wave velocity maps and site correction amplification based on topographic slope, and studies the application in the 2008 Wenchuan Ms8.0 earthquake.