人工主余震作用下桥墩结构损伤预测评估分析

主余震作用下,断层距(RJB)和余震次数的不同对结构造成的损伤也大不相同,进行主余震序列下桥梁损伤评估时需要考虑断层距、余震次数等影响因素.基于OpenSees平台,以一座连续梁桥为例,根据人工主余震构造时不同的影响因素,选用余震衰减和PGA调幅的人工主余震构造法构造主余震序列进行结构损伤分析,并与实际主余震事件的损伤...

Damage prediction and evaluation of bridge pier structures under artificial mainshock-aftershock sequences

Under mainshock-aftershock sequences, the structural damage caused by different fault distance (R_JB) and aftershock times are obviously different, so these influencing factors should be considered when evaluating the bridge damage under mainshock-aftershock sequences. Based on OpenSees platform, a continuous girder bridge was taken as an example in this paper. According to different influencing factors, the artificial main-aftershock sequences were selected to carry out the structural damage analysis. The damage results were compared with those of real main-aftershock events to study the feasibility of predicting structural damage by artificial main-aftershock sequences. The analysis results showed that:when considering the aftershock attenuation, the method based on modified PGA amplitude can well simulate the final damage of the structure under real main-aftershock sequences, and can reasonably predict the damage index of the structure. The influencing factors of fault distance and aftershock times should be considered when evaluating the damage of bridge under regional mainshock-aftershock sequences. The damage state of the bridge structure becomes more and more serious with the decrease in fault distance, and the structural damage increment increases with the increase in the number of aftershocks. Under artificial mainshock-aftershock sequences, the larger the fault distance, the smaller the error of incremental damage, and the closer the predicted damage state is to the actual state