考虑不确定性的山区中小跨径桥梁抗震性能分析  

Seismic Performance Analysis of Small and Medium Span Bridge Considering Uncertainty

作　　者：马健 熊江东 苏官林 段春雨 李立峰[3] MA Jian;XIONG Jiang-dong;SU Guan-lin;DUAN Chun-yu;LI Li-feng(Nujiang Meili Highway Greenway Construction Engineering Headquarters,Lushui 673200,China;Yunnan Comprehensive Transportation Development Center,Kunming 650032,China;School of Civil Engineering,Hunan University,Changsha 410082,China)

机构地区：[1]怒江美丽公路绿道建设工程指挥部,泸水673200 [2]云南省综合交通发展中心,昆明650032 [3]湖南大学土木工程学院,长沙410082

出　　处：《科学技术与工程》2025年第6期2564-2577,共14页Science Technology and Engineering

基　　金：云南省交通运输厅科技创新及示范项目(2022-82)。

摘　　要：为探讨中小跨径桥梁在设计、建造及服役期间中典型的不确定性因素对结构抗震性能的影响,以一座4跨连续小箱梁桥为工程背景,基于OpenSees建立非线性动力模型,分析了地震波不确定性、建模参数不确定性和构件抗震能力不确定性对关键构件地震动响应的影响机理。在此基础上,结合易损性分析理论,探讨了以上不确定性因素在构件易损性曲线的建立过程中的联动效应,进而量化了各类不确定性因素对结构抗震性能分析的影响程度。结果表明:构件的地震滞回曲线的差异主要由建模参数的不确定性造成,而峰值地震响应差异主要由地震动和建模参数的不确定性联合所导致;建模参数的不确定性和构件抗震能力的不确定性均会导致结构失效概率的增加,继而使得部分构件无法满足既定的损伤状态;考虑不确定性因素会增加桥梁系统易损性曲线的失效概率,且随着损伤程度的加深,不确定性的影响也会越大,使分析结果偏差30%以上。To explore the effects of typical uncertainty factors on the seismic performance of small-and medium-span bridges during design,construction,and service,a four-span continuous small box girder bridge was taken as the engineering background,and a nonlinear dynamic model was built based on OpenSees.The influence mechanisms of seismic uncertainty,modeling parameter uncertainty,and capacity uncertainty on the seismic demand of key components were analyzed.On this basis,combined with the theory of fragility analysis,the linkage effect of the above uncertainty factors in the establishment of component fragility curves was explored,and then the degree of influence of each type of uncertainty factors on the analysis of structural seismic performance was quantified.The results show that the differences in the seismic hysteresis curves of the components are mainly caused by the uncertainties of the modeling parameters,while the differences in the peak seismic response are mainly caused by the combined uncertainties of ground shaking and modeling parameters.The modeling parameter uncertainty and component seismic capacity uncertainty can lead to an increase in the probability of structural damage,which consequently makes some components unable to meet the required damage state.The consideration of the uncertainty factor increases the probability of failure of the bridge system susceptibility curve,and the effect of uncertainty increases as the degree of damage deepens,biasing the analysis results by more than 30 percent.

关 键 词：桥梁工程 中小跨径桥梁 易损性分析 不确定性 

分 类 号：U448.21[建筑科学—桥梁与隧道工程]