地震学报
地震學報
지진학보
ACTA SEISMOLOGICA SINICA
2014年
6期
1032-1042
,共11页
汶川地震%反应谱平台值%衰减关系%场地类型
汶川地震%反應譜平檯值%衰減關繫%場地類型
문천지진%반응보평태치%쇠감관계%장지류형
Wenchuan earthquake%response spectrum platform value%attenua-tion relationship%site condition
2008年汶川 Ms 8.0地震获得了大量的强震动记录,为研究反应谱特征参数衰减特性提供了重要的基础资料.本文对已知场地条件的174个台站的记录进行研究,计算其加速度反应谱并按照最小二乘分段拟合方法进行标定,进而拟合了反应谱平台值的衰减关系;对比分析了水平方向与竖直方向反应谱平台值的衰减特性,提出用“平台值的场地衰减影响系数”来定量研究不同场地类型对反应谱平台值的影响,用“衰减曲线下降速率”来定量分析不同衰减曲线的衰减速率.通过计算得出水平向Ⅰ,Ⅱ,Ⅲ类场地的平台值场地衰减影响系数平均值分别为0.5358,1和1.579,且Ⅲ类场地的加速度平台值衰减曲线的衰减速率最小.
2008年汶川 Ms 8.0地震穫得瞭大量的彊震動記錄,為研究反應譜特徵參數衰減特性提供瞭重要的基礎資料.本文對已知場地條件的174箇檯站的記錄進行研究,計算其加速度反應譜併按照最小二乘分段擬閤方法進行標定,進而擬閤瞭反應譜平檯值的衰減關繫;對比分析瞭水平方嚮與豎直方嚮反應譜平檯值的衰減特性,提齣用“平檯值的場地衰減影響繫數”來定量研究不同場地類型對反應譜平檯值的影響,用“衰減麯線下降速率”來定量分析不同衰減麯線的衰減速率.通過計算得齣水平嚮Ⅰ,Ⅱ,Ⅲ類場地的平檯值場地衰減影響繫數平均值分彆為0.5358,1和1.579,且Ⅲ類場地的加速度平檯值衰減麯線的衰減速率最小.
2008년문천 Ms 8.0지진획득료대량적강진동기록,위연구반응보특정삼수쇠감특성제공료중요적기출자료.본문대이지장지조건적174개태참적기록진행연구,계산기가속도반응보병안조최소이승분단의합방법진행표정,진이의합료반응보평태치적쇠감관계;대비분석료수평방향여수직방향반응보평태치적쇠감특성,제출용“평태치적장지쇠감영향계수”래정량연구불동장지류형대반응보평태치적영향,용“쇠감곡선하강속솔”래정량분석불동쇠감곡선적쇠감속솔.통과계산득출수평향Ⅰ,Ⅱ,Ⅲ류장지적평태치장지쇠감영향계수평균치분별위0.5358,1화1.579,차Ⅲ류장지적가속도평태치쇠감곡선적쇠감속솔최소.
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.