地震及次生突发灾害下公路桥梁网络韧性评估

Resilience assessment of highway bridge networks subjected to both earthquakes and earthquake-induced secondary emergencies

为明确地震作用和地震引发的次生突发灾害(EISE)对公路桥梁网络韧性的影响,首先,提出综合考虑区域地震危险性、EISE特性、桥梁易损性和交通流特性等因素的公路桥梁网络韧性分析方法;然后,分析EISE的响应机制,建立EISE对公路桥梁网络影响的模型,并发展地震及EISE作用下公路桥梁网络功能状态分析方法;最后,建立公路桥梁网络应对地震及EISE韧性评估指标,通过美国旧金山部分公路桥梁网络在地震及EISE作用下的韧性评估算例,验证该方法的实用性和有效性。结果表明:与单体桥梁相比,桥梁网络性能受地震动和EISE的相互作用,不仅受地震强度的影响,还受到地震位置的影响。所提方法能够合理评估桥梁网络应对地震EISE韧性。

In order to clarify the effects of earthquakes and EISE on resilience of highway bridge networks,a resilience analysis method was proposed,which considered factors like regional seismic hazards,characteristics of EISE,structural fragility of bridges and traffic characteristics,etc.Subsequently,response mechanism to EISE was analyzed,based on which EISE influence model on highway bridge network was established,and a method to analyze the network state under influence of both earthquakes and EISE was proposed.Finally,several resilience indexes were developed,and verification was conducted on a highway bridge network in San Francisco,California subjected to both earthquakes and EISE effect.The results show that compared with individual bridges,the performance of bridge network was influenced by interaction between earthquake motion and EISE,including not only the intensity,but also locations of earthquakes.And the proposed methodology can assess resilience of bridge networks against EIES.