摘要
本文采用水平向444条,竖向228条严格按我国抗震设计规范划分场地条件的实际强震记录,计算了不同情况下加速度反应谱竖向分量与水平分量的比值(V/H)的平均值,结果表明:(1)V/H随周期变化明显。在短周期,有1个1.0左右的峰值,在周期0.2～1.0s间有1个0.4左右的低谷,在2s以后的长周期,V/H趋近1个0.6左右的常数。(2)V/H值与震中距也有很大关系,在震源附近竖向反应谱与水平向反应谱很接近,V/H均值在周期长于2s时达到了0.9。(3)它与场地条件也有很大关系,短周期处,Ⅰ类场地V/H峰值为0.7,Ⅱ、Ⅲ类场地V/H峰值为1.1,长周期处则随场地类别由Ⅰ,Ⅱ到Ⅲ类,V/H由大到小。建议抗震设计规范修订时应考虑对竖向反应谱的规定予以修正,文中给出了建议方案。
In this paper, horizontal 444 and vertical 228 strong motion records classified into 4 site types according to Code for Seismic Design of Buildings are used to calculate the average ratios of the vertical and horizontal response spectra(V/H). The results show that (1) V/H varies with period in the following general pattern:the H/V reaches a peak 1.0 or so, at short period range, decreases with period to a sag of near 0.4 at period of 0.2～1.0 sec, and turns to increase in the longer period, reaches a stable value near 0.6. (2) The V/H varies with epicenter distance: the vertical and the horizontal response spectra are not obviously different near epicenter, the ratio reaches 0.9 in long period. (3) The ratio varies with site types too: at short period, the V/H is 0.7 in site type Ⅰ, 1.1 in site types Ⅱ and Ⅲ. At long period, the V/H decreases with site types from Ⅰ,Ⅱ to Ⅲ. The vertical response spectra should be revised in seismic design code. In the paper, a provision is proposed.
出处
《地震工程与工程振动》
CSCD
北大核心
2004年第5期33-38,共6页
Earthquake Engineering and Engineering Dynamics
基金
国家社会公益研究专项(2002DIB30076)
