摘要
基于风险理论,提出一种用概率方法来考虑洪水和地震作用下砌体结构的失效风险评估方法。根据村镇建筑结构在灾害作用下的性能要求,量化结构的性能指标,分析村镇建筑结构在洪水冲刷和地震联合作用下的易损性,综合考虑洪水冲刷、地震的灾害危险性和结构易损性,通过易损性函数与联合灾害概率密度函数在灾害域上积分,获得结构在不同破坏状态下的超越概率,引入损失比和结构累计失效概率,进而获得全性能状态下的可靠度指标,并与目标可靠度指标对比,进行结构性能评估。算例展示了本文方法的建立过程,结果表明:冲刷对结构轻微破坏和中度破坏的易损性影响较小,对严重破坏和倒塌状态的易损性影响较大;洪水冲刷对结构抗震性能具有较大的影响,相比于仅考虑地震作用下,同时考虑洪水冲刷和地震联合作用时,结构各种破坏状态下的失效概率均有所增加,且随着破坏程度的加剧,冲刷对结构失效概率的影响越来越大。
Based on the risk theory,a probabilistic method for considering the failure risk assessment of masonry structures under flood and earthquake is proposed. According to the performance requirements of the building structure in villages and towns under the action of disasters,the performance index of the structure is quantified,and the structural vulnerability of the building structure in villages and towns under the combined action of flood scouring and earthquake is analyzed. Considering scouring hazard,earthquake hazard and structural fragility,the probability of exceedance of the structure under different failure states is obtained by integrating of the fragility function and the joint disaster probability density function in the disaster domain. Furthermore,the loss ratio and the cumulative failure probability of the structure are introduced to obtain the reliability index under the full operation state.Finally,structural assessment is performed in comparison with target reliability indicators. The example illustrates the establishment process of the method. The results show that the scouring has little effect on the fragility of structural minor damage and moderate damage,and has a great influence on the severe damage and collapse. The flood scouring has a great influence on the seismic performance of structures. When considering the combined effect of flood scouring and earthquake,compared with single earthquake effect,the failure probability in each failure state of the structure greatly increases,and as the degree of damage increasing,the impact of scouring on the probability of structural failure is getting bigger and bigger.
作者
吕光辉
李钢
董志骞
李宏男
LYU Guanghui;LI Gang;DONG Zhiqian;LI Hongnan(State Key Laboratory of Costal and Offshore Engineering,Dalian University of Technology,Dalian 116024,China;College of Civil Engineering,Shenyang Jianzhu University,Shenyang 110168,China)
出处
《防灾减灾工程学报》
CSCD
北大核心
2022年第2期294-302,309,共10页
Journal of Disaster Prevention and Mitigation Engineering
基金
国家重点研发计划项目(2018YFD1100404)
大连高层次人才创新支持计划项目(2017RD04)资助。
关键词
冲刷
地震
多灾害
可靠度指标
风险评估
scouring
earthquake
multiple disasters
reliability index
risk assessment
