钢筋混凝土简支T梁桥加固后的体系时变可靠度

为分析钢筋混凝土简支T梁桥加固后承栽能力的变化趋势，对钢筋混凝土简支T梁桥上部结构加固前后的体系时变可靠度进行了计算分析．在计算过程中，推导了构件加固前后正截面承载能力的统计参数，并确定了其分布类型，然后利用蒙特卡罗法编制了串联方法计算加固后桥梁上部结构体系时变可靠度的计算程序．计算结果表明，在常用的4种桥梁上部结构加固方法中，体外预应力加固上部结构后的可靠度指标上升幅度最大，且桥梁承载能力再次衰减的速率最小．

Time-Varying Reliability Analysis of the Whole Reinforced Simple T-Bridge

The time-varying reliability of pre-reinforced and post-reinforced simple T-girder bridge was calculated to evaluate the trend in carrying capacity. During the analysis, the statistical parameters of pre-reinforced and post- reinforced T-girder were derived. Classical probability distribution was also used to program for calculating the time- varying reliability of the whole bridge connected by the series connection method with Monte-Carlo simulation. With this program, the time-varying reliability analyses of prereinforced and post-reinforced bridge structures were discussed. The results show that the external prestressing method increases the reliability index with the maximum ampli- tude compared with the other three fastening methods. The post-reinforced bridge with the external prestressing method has the minimum decay rate.