摘要
目前桥梁结构抗多灾害研究主要集中在桥梁结构冲刷与主余震方面,对地震和滑坡链式灾害作用下桥梁结构易损性的研究较少。建立了地震和滑坡联合作用下桥梁结构性态分析框架并以某三跨连续梁为例,采用OpenSees软件建立了全桥非线性有限元模型,考虑了桩土相互作用的影响,并基于非线性时程分析研究了滑坡体积与滑坡运动距离等因素对桥梁结构易损性曲线的影响。结果表明:在地震和滑坡联合作用下桥梁结构累积损伤明显增大;在滑坡运动距离为150 m范围内,桥梁结构失效概率明显增大,当滑坡运动距离超过250 m时,桥梁结构失效概率增幅较小;当PGA为1g且滑坡运动距离为100 m时,体积为1×10^(7 )m^(3)量级的滑坡对桥梁结构破坏作用最大,导致桥梁结构完全失效的概率将增加60%以上;地震和滑坡的存在会显著增大桥梁结构在不同地震动水平下的失效概率,在选址时应予以充分考虑。
The disasters-resistant research on bridge structure mainly focuses on the mainshock-aftershock and erosion performance.Few studies are proposed on seismic fragility analysis of bridges under disaster chain.First,this paper proposes a framework of bridge performance analysis based on cumulative damage under earthquake and landslide.By using a typical three-span continuous girder bridge in the western mountain area as an example,the nonlinear finite element model was built.Then,based on the nonlinear time history analysis,the cumulative damage of bridge structure under the combined action of earthquake and landslide was analyzed by a probability-based method,and the seismic vulnerability curve was obtained to evaluate the seismic performance of bridge structure.Finally,the effect of the landslide volume and the landslide movement distance on the seismic performance of bridges was studied.The results show that the cumulative damage of bridge structure increases obviously under the disaster chain action of earthquake and landslide,and the seismic demand of structure increases greatly.The failure probability of the bridge structure increases significantly when the landslide distance is 150 m,and it starts to be stable after the distance exceeds 250 m.When PGA=1g,landslide movement distance is 100 m,the landslide with the volume of 1×10^(7) m^(3) has the largest damage effect on the structure,and the probability of complete damage increases by more than 60%.The existence of earthquake landslides will significantly increase the failure probability of bridge structures under different ground motion levels,which should be considered in site selection and safety fortification.
作者
程周炳
朱维元
庞于涛
蔡黎
CHENG Zhoubing;ZHU Weiyuan;PANG Yutao;CAI Li(Department of Construction and Campus Planning,China University of Geosciences(Wuhan),Wuhan 430074,China;Faculty of Engineering,China University of Geosciences(Wuhan),Wuhan 430074,China)
出处
《安全与环境工程》
CAS
CSCD
北大核心
2024年第4期133-141,共9页
Safety and Environmental Engineering
基金
国家自然科学基金项目(51708527)。
关键词
地震和滑坡联合作用
连续梁桥
结构易损性分析
云图法
失效概率
combination effect of earthquake and landslide
continuous girder bridge
structural vulnerability analysis
cloud analysis
failure probability
