汶川地震和东日本大地震反应谱比较与结构Pushover分析

Spectrum Comparison of Wenchuan Earthquake and the Great East Japan Earthquake and Pushover Analysis of Frame Structures

为对比分析5·12汶川地震和3·11东日本大地震的加速度反应谱和结构地震反应特征,挑选132条汶川地震和404条东日本大地震中Ⅱ类场地上的水平向加速度记录,进行统计分析。根据这两次大地震的标准加速度反应谱,给出了拟合谱曲线。将所得拟合谱作为需求谱,分别对6层框架结构和20层框架结构进行了Pushover分析,比较在上述两次大地震下不同框架结构地震反应的差异。结果表明:东日本大地震记录比汶川地震记录具有较明显的长周期地震动特征;两次地震记录的区别在高层框架结构的地震反应上表现得更加明显,东日本大地震记录对具有较长自振周期的结构的地震反应影响更为显著。

To make the comparative analysis of the acceleration spectrums of 5. 12 Wenchuan Earthquake and 3. 11 Great East Japan Earthquake and make the seismic response analysis of structures,132 horizontal acceleration records of Wenchuan Earthquake and 404 horizontal acceleration records of the Great East Japan Earthquake were selected. The site type is Ⅱ. The standard acceleration response spectrums and the fitting response spectrums of the two earthquakes were got by statistical analysis. Then the fitting response spectrums were used as the demand spectrums to do the Pushover analysis on a 6-story frame structure and a 20-story frame structure. The seismic response differences between the two structures under the two selected earthquakes were analyzed. The results show that compared to the Wenchuan Earthquake,the Great East Japan Earthquake presents long-period characteristics. Also,more obvious differences between the two earthquakes are shown on high-rise frame structures. The Great East Japan Earthquake has greater effects on long-period structures.