Attenuation characteristic of the response spectrum platform value for 2008 Wenchuan Ms8.0 earthquake
Wan Wei
Bo Jingshan
Guo Xiaoyun
Abstract：After the 2008 Wenchuan Ms 8.0 earthquake,a large volume of strong motion records were acquired,which provides important basic data for the study on attenuation characteristics of seismic response spectrum parameters.This paper calculates the acceleration response spectra of strong motion records from 174 seismic stations with known site conditions.The spectra are calibrated via piecewise fitting with the least-squares method in order to fit the attenuation re-lationships of a response spectrum platform value.This paper also comparative-ly analyzes the attenuation characteristics of both vertical and horizontal re-sponse spectrum platform values so as to demonstrate how the quantitative study of site condition affects response spectrum platform values by means of the site attenuation influence coefficient of platform value.It also quantitatively analyzes the attenuation rates of different attenuation curves by means of their descending rates. The calculation results show that the site attenuation influence coefficients of horizontal platform value has an average value that is different for the three site types.The value for site type Ⅰ is 0.535 8,type Ⅱis 1;and type Ⅲ is 1.579,which is the minimum attenuation rate of the plat-form in all site types.
Keywords：Wenchuan earthquakeresponse spectrum platform valueattenua-tion relationshipsite condition
Publication Date：2014-01-01
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：11( 1032-1042 )