摘要
目的研究桥梁可靠度计算的车辆荷载取值,提出对既有桥梁结构时变可靠度指标的既有桥梁评估目标期内车辆荷载效应最大值分布参数的修正系数.方法基于结构时变可靠度理论,按照设计基准期和目标评估期的等概率分位值原则,分析钢筋锈蚀导致桥梁结构抗力衰减的特性以及在结构服役期缩短情况下的桥梁车辆荷载模型.结果考虑既有结构抗力退化,计算时变可靠度指标β(t),利用迭代法给出了既有桥梁结构时变可靠度计算的车辆荷载模型和分布参数的修正系数.结论对于既有桥梁时变可靠度计算的荷载取值,在考虑结构时变抗力退化模型的基础上,计算初始评估期内的β(t)与目标可靠度指标βT对比得到新的评估目标期,经过迭代计算结构各时段可靠度指标以及车辆荷载效应最大值分布的修正系数.
This paper analyzes the variable load in lifetime performance reliability of existing concrete bridges.Through calculating the time-dependent reliability index,a practical method of modifying coefficients of maximum distribution parameters in vehicle loads has been developed.According to the design and evaluation reference period of probability value points,this study analyzed the characteristic of the concrete bridges subjected to corrosion leads to resistance degradation and the load model of short service life of the maximum distribution parameters in vehicle loads are deduced.Through calculating the reliability index β（t）,the coefficients of maximum distribution parameters in vehicle loads has been derived.For the existing concrete bridges,different reliability indexes and load model of service life in evaluation period should be considered,the reliability index β（t） of evaluation period and βT in design reference period are calculated.At last,by means of iteration methods,the coefficients of maximum distribution parameters in vehicle loads are revised during the time-dependent reliability analysis of existing concrete bridges.
出处
《沈阳建筑大学学报（自然科学版）》
CAS
北大核心
2010年第5期828-832,共5页
Journal of Shenyang Jianzhu University：Natural Science
基金
贵州省优秀科技教育人才省长专项基金项目(200703)
关键词
桥梁结构
抗力
车辆荷载模型
时变可靠度
bridge structure
resistance
vehicle load models
time-dependent reliability
