摘要
建立列车荷载与环境共同作用下考虑简支箱梁上CRTSⅡ型轨道板预应力损失的、不同位置处单一失效模式的横向抗裂功能函数以及多重失效模式下的体系功能函数,发展基于三阶矩方法的、分别考虑单一以及多重失效模式的轨道板横向抗裂时变可靠度分析方法。算例结果表明:本文方法与蒙特卡洛方法相比,在计算精度几乎相同的情况下,大幅提高了计算效率。时变可靠度同时表明:轨道板不同位置处的混凝土抗裂可靠度相差较大,轨下截面下缘混凝土抗裂可靠度处于最低水平,较好地预测了轨道板服役的真实状态。建议提高轨道板薄弱部位混凝土抗裂可靠度设计值,以进一步提升体系可靠度。
This paper proposed individual failure performance function with different positions of transverse crack resistance of CRTSⅡtrack slab on the simply-supported box girder and multiple failure performance functions, which are under combined action of train load, environment and prestress loss. Using these performance functions, the third-moment method was developed to conduct time-dependent reliability of individual failure and multiple failure models of transverse crack resistance of track slab. The results of numerical examples demonstrate that the developed method is much more efficient than Monte Carlo simulation method without loss of accuracy;and the results of time-dependent reliability also show that the crack resistance reliability index of concrete at different locations of track slab has big difference and the reliability index of transverse cracking of lower flange of track slab is at the lowest level, which can sufficiently predict the real state of service of the track slab. It is suggested that the reliability design value be improved for the crack resistance of weak position of the track slab to further enhance the system reliability index.
作者
邹红
卢朝辉
余志武
ZOU Hong;LU Zhaohui;YU Zhiwu(School of Civil Engineering, Central South University, Changsha 410075, China)
出处
《铁道学报》
EI
CAS
CSCD
北大核心
2019年第4期177-185,共9页
Journal of the China Railway Society
基金
国家自然科学基金(51820105014)
关键词
CRTSⅡ型轨道板
轨道板横向抗裂
时变可靠度
体系可靠度
矩法
CRTSⅡballastless track slab
transverse crack resistance of track slab
time-dependent reliability
system reliability
method of moment
