大跨度铁路悬索桥变形验算中的列车荷载折减系数  

Train Load Reduction Factors of Deflection Calculation for Long-span Railway Suspension Bridge

作　　者：王兴超 李文杰 WANG Xingchao;LI Wenjie(Faculty of Infrastructure Engineering,Dalian University of Technology,Dalian Liaoning 116024,China;China Communication Construction Co.Ltd.,Beijing 100088,China)

机构地区：[1]大连理工大学建设工程学部,辽宁大连116024 [2]中国交通建设集团有限公司,北京100088

出　　处：《铁道建筑》2022年第12期110-116,共7页Railway Engineering

摘　　要：列车静活荷载下多线大跨度铁路桥梁的挠度验算属于正常使用极限状态设计的内容。正常使用极限状态与承载能力极限状态的失效准则和控制标准是不同的,因此,将大跨度铁路桥梁承载能力极限状态设计的列车活荷载折减系数用于正常使用极限状态设计是不合理的。本文以一座铁路悬索桥为研究对象,通过对列车的随机模拟研究多线大跨度铁路桥梁主梁挠度的概率特征,根据正常使用极限状态设计可变荷载频遇值的概念,确定多线大跨度桥梁挠度验算的列车静活荷载折减系数。结果表明,双线、三线和四线大跨度铁路桥梁挠度验算时列车静活荷载的折减系数均可取0.25。The deflection calculation of multi-line long-span railway bridge under static live load of train is a part of serviceability limit state design.The failure criterion and control level of limit value of serviceability and ultimate limit state are different,so it is inappropriate to use the load reduction factor for ultimate limit state design in serviceability limit state design.In this paper,the probabilistic characteristics of the deflection of main girders of multi-line long-span railway bridges were studied by stochastic simulation of train on a suspension bridge.The frequent combination of the serviceability limit state design was adopted to determine the reduction factors of static live load of train for the deflection calculation of multi-line long-span bridges.It shows that the reduction factors of the static live load of train of the deflection calculation for two-line,three-line and four-line long-span railway bridges can all be taken as 0.25.

关 键 词：铁路桥梁 悬索桥 折减系数 统计分析 历程曲线 列车荷载 挠度 

分 类 号：U441.2[建筑科学—桥梁与隧道工程]