美国西部水平向基岩长周期地震动反应谱衰减关系研究

Attenuation relationship of long period ground motion response spectrum of horizontal bedrock in western United States

利用新近补充的美国西部地区宽频带速度基岩记录,对水平向基岩5%阻尼比地震动反应谱衰减关系的长周期段(T=3~10 s)进行了重新拟合,并将其与短周期反应谱衰减关系(T=0.04~6.00 s)在周期2.0 s附近进行对接。基于新得到的长周期范围0.04~10.00 s的衰减模型,对离散标准差、远场区域归一化反应谱特性等进行了分析。新得到的衰减关系使用的技术方法和强震数据集等与GB 18306—2015《中国地震动参数区划图》项目编图采用的相一致,适用范围为M s5.0~8.0,震中距0~500 km。

Based on the newly supplemented broadband velocity response records of bedrock in the western United States,the long period(T=3-10 s)part of 5%damping ratio seismic response spectrum attenuation relationship of horizontal bedrock was re-fitted,and it was connected with the short period(T=0.04-6.00 s)part near the period of 2.0 s.Based on the new obtained attenuation model in the long period range of 0.04-10.00 s,discrete standard deviation and far-field normalized response spectrum characteristics were analyzed.The technical method and strong earthquake data set used in the new obtained attenuation relationship were consistent to those used in the seismic parameter zonation map of China(GB 18306—2015)with the applicable range of M s5.0-8.0 and the epicentral distance of 0-500 km.