近场脉冲效应对强度折减系数的影响分析  

Adjacent-field velocity pulse effect on strength reduction factors

作　　者：翟长海[1] 谢礼立[1] 

机构地区：[1]哈尔滨工业大学,黑龙江哈尔滨150090

出　　处：《土木工程学报》2006年第7期15-18,42,共5页China Civil Engineering Journal

基　　金：国家自然科学基金重点项目(50538050);高等学校博士学科点专项科研基金(20030213042);黑龙江省自然科学重点基金(ZJG03-03)

摘　　要：近场脉冲型地震动具有十分巨大的潜在破坏性。以集集地震提供的近场地震动记录为基础,利用统计分析的方法研究近场脉冲效应对强度折减系数的影响规律,并给出近场脉冲效应影响强度折减系数的修正公式。结果表明:在长周期频段,近场速度脉冲型地震动给出的强度折减系数与一般地震动给出的强度折减系数趋向于一致,而在中短周期频段,近场速度脉冲型地震动给出的强度折减系数显著小于一般地震动给出的强度折减系数,这表明如果用现有的强度折减系数模型(都是远场地震动给出的强度折减系数)应用到近场地区,则可能是比较危险的;对某一给定的周期,随延性系数的增大,近场速度脉冲型地震动给出的强度折减系数与一般地震动给出的强度折减系数的差异也越大。Strong adjacent-field pulse ground motions pose severe potential damage to the structures. Based on the large number of adjacent-field velocity-pulse ground motions recorded in the Chi-Chi earthquake （Taiwan September 20, 1999） , the effect of adjacent-field velocity-pulse on the strength reduction factors is statistically investigated and expressions for the modification of the strength reduction factors are established. It is concluded that in the long period range, the strength reduction factors for the adjacent-field velocity-pulse ground motions tend to be consistent with those for far-field ground motions. But, in the short or medium period range, the strength reduction factors for the adjacent-field velocity-pulse ground motions are significantly smaller than those from the far-field ground motions, making it unsafe, in adjacent areas, to use the current strength reduction factors, which were obtained for far-field ground motions. For a given period, the adjacent-field effect on the strength reduction factors increases with the structure ductility coefficient.

关 键 词：强度折减系数 近场脉冲效应 集集地震 统计分析 

分 类 号：P315.9[天文地球—地震学]