CRTSⅡ型板式无砟轨道轨道板横向可靠度的计算方法研究

摘要

在无砟轨道建造和运营过程中存在着诸多不确定性，因而设计轨道结构时应使用可靠度理论计算分析结构的可靠性。应用可靠度理论分析时，在最不利状况下将轨道板视为一系列串联的全支撑宽轨枕。考虑列车荷载和温度梯度荷载两种主要荷载分别服从正态分布与威布尔分布，其荷载效应可分别按轨枕全支撑受力模式及Westgaard公式计算。考虑到荷载、抗力及计算模式的不确定性，假定了各参数的均值与变异系数，对轨道板横向宽轨枕单元的轨下截面和板中截面的可靠度分别进行了计算，其可靠度指标均满足结构可靠性要求。%T here are many uncertainties in the ballastless track construction and operation and the reliability theory should be applied in the track structure design to analyze the structure reliability. By applying the reliability theory, the track slab could be considered as a series of connected and fully supporting wide sleeper under the most adverse conditions. T he train load follows normal distribution and the temperature gradient load follows W eibull distribution, the load effects of which can be calculated by using the full supporting sleeper mode and W estgaard formula respectively. Considering the uncertainties of the loads,resistance and calculation mode,the section reliability under the rail and in middle of track slab for transverse wide sleeper units were calculated by assuming the mean values and variation for each parameter,the reliability indexes of which meet the structure demands.