不同跨径桥梁车辆荷载分项系数及可靠度  

Partial Factors of Vehicle Loads and Reliability Analysis of Bridges with Different Spans

作　　者：杨晓艳[1] 贡金鑫[1] 冯云芬[2] 

机构地区：[1]大连理工大学土木工程学院,辽宁大连116024 [2]聊城大学建筑工程学院,山东聊城252059

出　　处：《中国公路学报》2015年第6期59-66,共8页China Journal of Highway and Transport

基　　金：国家重点基础研究发展计划("九七三"计划)项目(2015CB057703)

摘　　要：以可靠度理论和实测车辆荷载数据为基础,推导了考虑桥梁跨径对车辆荷载分项系数的影响。根据近年中国车辆荷载实测数据,对不同跨径简支和连续桥梁的车辆荷载效应进行计算,建立车辆荷载效应的概率模型;按照相同超越概率的原则,得到不同跨径桥梁车辆荷载效应标准值的跨径影响系数,在此基础上确定了不同跨径桥梁结构的车辆荷载分项系数与跨径的关系,并采用一次二阶矩可靠度方法计算了其可靠指标。结果表明:按相同超越概率原则确定的车辆荷载效应标准值的跨径影响系数和车辆荷载分项系数随桥梁跨径的减小而增大;给出的考虑跨径影响的车辆荷载分项系数计算公式更合理。Based on reliability theory and recently measured vehicle load data,the influence of bridge span on partial factors of vehicle load was derived.According to recently vehicle load data measured in China,the vehicle load effects of multi-span simply supported and continuous twoequal span bridges were calculated,as well as the probability models were founded.In accordance to the principle of the same exceeding probability,influence factors of span for characteristic values of vehicle load effects with various spans were obtained,based on which,the relationship between the partial factors of vehicle load effects and the span of bridge was determined.Reliability analysis for bridge design as per the determined vehicle load partial factor-span relationship was made with First-order Second-moment method（FOSM）.The results show that the span influence factor and vehicle load partial factor for characteristic value of vehicle load effect,which were determined based on the equal exceeding probability,increase with the decrease of the span of bridge.The proposed span dependent partial factor calculation formula for vehicle load for bridge design is more reasonable.

关 键 词：桥梁工程 荷载效应 概率模型 分项系数 可靠度 

分 类 号：U441.2[建筑科学—桥梁与隧道工程]