沪通长江大桥主航道桥铁路活载加载标准研究  

Study of Loading Criterion of Railway Live Loads on Main Ship Channel Bridge of Hutong Changjiang River Bridge

作　　者：郑清刚[1] 张燕飞[1] 肖海珠[1] 高宗余[1] 

机构地区：[1]中铁大桥勘测设计院集团有限公司,湖北武汉430056

出　　处：《桥梁建设》2016年第6期51-55,共5页Bridge Construction

基　　金：中国铁路总公司科技研究开发计划项目(2014G004-B)~~

摘　　要：沪通长江大桥主航道桥（主跨1 092m双塔斜拉桥）主跨跨度和桥长均超过实际列车长度,依据现行规范活载按无限长加载不合理。鉴于此,设计过程中开展我国铁路活载标准和客货运铁路活载现状分析,基本确定该桥依据到发线有效长度计算活载长度的加载标准。对分别按照5 000t牵引定数加载（L=614.25m）、按照到发线长度确定的车长加载（L=970m）和按照无限长加载3种模式（依次为活载Ⅰ~Ⅲ）下结构的响应进行对比分析,结果表明：与活载Ⅰ相比,活载Ⅱ和活载Ⅲ作用下桥塔弯矩、位移等指标增大5%~18%,活载Ⅲ与活载Ⅱ作用下结构响应差别相对较小;采用活载Ⅱ加载取值合理,同时结构具有足够的安全储备。The main span length and the length of the main ship channel bridge （a double-py- lon cable-stayed bridge with the main span of 1 092 m） of the Hutong Changjiang River Bridge is all longer than the actual length of the trains to travel on the bridge. The loading of the live loads, such as the train loads, on the bridge according to the infinite length as specified in the current codes is not reasonable. In regard of this problem, in the design of the bridge, the railway live load standards and the current practice of the passenger and freight railway live loads in China are ana- lyzed and the loading criterion of calculating the live load length for the bridge according to the effective length of the arrival and departure track is basically determined. The structural responses of the bridge according to the three types of the loading modes （successively the live loads I-Ⅲ）, such as the loading according to the 5 000 rating tonnage of traction （L=614.25 m）; the loading according to the train length determined by the length of the arrival and departure track （L=970 m） and the loading according to the infinite length, are compared and studied. The results demon- strate that as compared to the live load I, the indices of the bending moment and displacement of the pylons under the action of the live loads Ⅱ and Ⅲ increase by 5%-18% and the differences of the structural responses under the action of the live loads Ⅲ and Ⅱ are relatively little. The loading according to the values of the live load Ⅱ is reasonable and at the same time, the structure itself can have sufficient safety margin.

关 键 词：斜拉桥 公路铁路两用桥 钢桁梁 铁路活载 到发线有效长度 加载标准 

分 类 号：U448.27[建筑科学—桥梁与隧道工程] U442.52[交通运输工程—道路与铁道工程]