地震动中输入能量的探讨  

Probe into Input Energy for the Characterization of Earthquake Ground Motions

作　　者：丁玉春[1] 朱晞[1] 

机构地区：[1]北京交通大学土木建筑工程学院,北京100044

出　　处：《北京交通大学学报》2007年第4期49-51,共3页JOURNAL OF BEIJING JIAOTONG UNIVERSITY

基　　金：高等学校博士学科点专项科研基金资助项目(20040004025)

摘　　要：用能量的方法研究在单自由度体系中(SDOF),结构在差异较大的软土和硬土场地上,承受近断层实际地震时,自振周期T=0.8 s的结构在地震激励下的瞬时输入能量和总输入能量.得出对于脉冲型地面运动,结构达到最大输入能所需的响应时间要比长持时地面运动所需的时间短,而结构耗散的能量要比长持时地面运动耗散的能量大得多的结论.从瞬时输入能量以及总输入能量两个角度考虑输入能,认为瞬时输入能是地震设计中不可忽视的.计算得出,结构进入弹塑性阶段后,在双线性的滞回模型的假定条件下,结构延性系数不同时,两种场地所得的平均弹塑性等效速度谱,并进行了场地条件对结构输入能影响的分析比较.发现软土场地上的平均等效速度谱较好体现了结构的自振周期,应避开场地的卓越周期.The energy characteristics of an elastic - perfectly - plastic SDOF system for the selected near fault ground motions of soft and hard sites have been investigated in this paper. The momentary and accumulative energy of the structure with the period of 0.8s are activated by the earthquake, and it is found that the energy consumed by the structure for the pulse-type ground motions is much larger than that for the long duration ground motions. The momentary input energy can not be neglected from the view of the momentary and accumulative energy of the structure . The averaged elastic-plastic input equivalent velocity spectrum with the assumed bilinear hysterical model and the different ductility coefficients show that the period of the structure must keep away from the predominant period of the sites.

关 键 词：场地 瞬时输入能量 总能量 等效速度 

分 类 号：P315[天文地球—地震学]