The Qianguo Ms5. 8 earthquake swarm of 2013 occurred in Qianguo, Jilin Province, China. There are five earthquakes with Ms ≥5. 0 in the Qianguo earthquake swarm, with magnitudes of Ms 5. 5, Ms 5. 0, Ms 5. 3, Ms 5. 8 ...The Qianguo Ms5. 8 earthquake swarm of 2013 occurred in Qianguo, Jilin Province, China. There are five earthquakes with Ms ≥5. 0 in the Qianguo earthquake swarm, with magnitudes of Ms 5. 5, Ms 5. 0, Ms 5. 3, Ms 5. 8 and Ms 5. 0. In this study, the far-field seismic radiated energy characteristics of the earthquakes are compared based on the source spectrum and the ground motion spectrum of the earthquake swarm. The ground motion spectrum of the five earthquakes at Changchun seismic station (CN2), which is the national standard station, is first investigated with the recorded ground motions, and then the far-field seismic radiated energy is calculated and combined with the relationships of the source spectrum to describe the variable characteristics of the Qianguo earthquake swarm. Research results indicate that the second earthquake (No. 2) with Ms5. 0 is the key event of the earthquake swarm, which occurred on October 31, the same day following the first Ms5. 5 earthquake (No.l). In fact, the magnitude of event No. 2 decreased compared to event No.l, which did not agree with its large far-field seismic radiated energy. It needs to be pointed out that event No. 2 was the turning point event of the Qianguo earthquake swarm, as being a significant transition before the largest Ms5. 8 earthquake.展开更多
以4种场地土条件下40条强震记录为输入,分析了弹塑性单自由度(Single Degree of Freedom,SDOF)系统的地震输入能量谱,并对地震动强度和SDOF系统参数对地震输入能量谱的影响进行了研究。结果表明:能量谱峰值主要由地震动强度决定,阻尼比...以4种场地土条件下40条强震记录为输入,分析了弹塑性单自由度(Single Degree of Freedom,SDOF)系统的地震输入能量谱,并对地震动强度和SDOF系统参数对地震输入能量谱的影响进行了研究。结果表明:能量谱峰值主要由地震动强度决定,阻尼比和延性系数有很大影响。在长周期范围,延性系数一定时,随着阻尼比的增大,能量谱值也有所增大;随延性系数增大,能量谱值随阻尼比增加而增大的趋势有所减缓。采用归一化方法,根据能量谱的特征建议了简化三段式地震输入能量谱,并根据能量谱分析结果的统计,建议了弹塑性SDOF系统能量谱峰值和能量谱曲线参数的确定方法。展开更多
基金funded by the National Natural Science Foundation,China(Grant No.41404045,No.41504047)
文摘The Qianguo Ms5. 8 earthquake swarm of 2013 occurred in Qianguo, Jilin Province, China. There are five earthquakes with Ms ≥5. 0 in the Qianguo earthquake swarm, with magnitudes of Ms 5. 5, Ms 5. 0, Ms 5. 3, Ms 5. 8 and Ms 5. 0. In this study, the far-field seismic radiated energy characteristics of the earthquakes are compared based on the source spectrum and the ground motion spectrum of the earthquake swarm. The ground motion spectrum of the five earthquakes at Changchun seismic station (CN2), which is the national standard station, is first investigated with the recorded ground motions, and then the far-field seismic radiated energy is calculated and combined with the relationships of the source spectrum to describe the variable characteristics of the Qianguo earthquake swarm. Research results indicate that the second earthquake (No. 2) with Ms5. 0 is the key event of the earthquake swarm, which occurred on October 31, the same day following the first Ms5. 5 earthquake (No.l). In fact, the magnitude of event No. 2 decreased compared to event No.l, which did not agree with its large far-field seismic radiated energy. It needs to be pointed out that event No. 2 was the turning point event of the Qianguo earthquake swarm, as being a significant transition before the largest Ms5. 8 earthquake.
文摘以4种场地土条件下40条强震记录为输入,分析了弹塑性单自由度(Single Degree of Freedom,SDOF)系统的地震输入能量谱,并对地震动强度和SDOF系统参数对地震输入能量谱的影响进行了研究。结果表明:能量谱峰值主要由地震动强度决定,阻尼比和延性系数有很大影响。在长周期范围,延性系数一定时,随着阻尼比的增大,能量谱值也有所增大;随延性系数增大,能量谱值随阻尼比增加而增大的趋势有所减缓。采用归一化方法,根据能量谱的特征建议了简化三段式地震输入能量谱,并根据能量谱分析结果的统计,建议了弹塑性SDOF系统能量谱峰值和能量谱曲线参数的确定方法。