WJ-8型小阻力扣件纵向阻力温变特性研究  

Temperature-dependent characteristics of longitudinal resistance of WJ-8 type small resistance fastener

作　　者：黄志斌 曾志平[1,3] 李桩[1,4] 饶惠明 肖燕财 叶梦旋 HUANG Zhibin;ZENG Zhiping;LI Zhuang;RAO Huiming;XIAO Yancai;YE Mengxuan(School of Civil Engineering,Central South University,Changsha 410075,China;Southeast Coastal Railway(Fujian)Co.,Ltd.,Fuzhou 350001,China;MOE Key Laboratory of Engineering Structures of Heavy Haul Railway(Central South University),Changsha 410075,China;China Railway Electrification Engineering Group Co.,Ltd.,Beijing 100036,China)

机构地区：[1]中南大学土木工程学院,湖南长沙410075 [2]东南沿海铁路福建有限责任公司,福建福州350001 [3]重载铁路工程结构教育部重点实验室(中南大学),湖南长沙410075 [4]中铁电气化局集团有限公司,北京100036

出　　处：《铁道科学与工程学报》2023年第5期1687-1694,共8页Journal of Railway Science and Engineering

基　　金：中国铁路南昌局集团有限公司科技研究开发计划课题(202007)。

摘　　要：为评估高速铁路桥上无缝线路扣件对服役环境的适应性,以WJ-8型小阻力扣件为例,开展一系列室内纵向阻力试验。设置-30~60℃的环境温度和90~120 N·m的螺栓扭矩,在标准组装状态下按照10 kN/min的恒定速率加载,实时记录纵向力值及钢轨纵向位移值,每个工况加载4次。试验获得了4个不同扭矩和10个不同温度组合工况下的扣件纵向阻力-位移变化特征,分析得到温度、扭矩和纵向滑移阻力三者之间的映射关系。研究结果表明:1)不同工况下,扣件纵向阻力随位移的增大呈幂指型函数递增关系;不同扭矩作用下,扣件纵向滑移阻力随温度升高呈指数型函数递增关系;不同温度作用下,扣件纵向滑移阻力随扭矩增大呈线性递增关系。2)扭矩作用和温度作用对小阻力扣件纵向阻力均有影响,但扭矩作用基本不影响扣件阻力对温度变化的敏感性,反之亦然。3)当温度上升至40℃以后,在规范建议的90~120 N·m扭矩下,纵向滑移阻力均不再满足4±1 kN的要求。建议高温环境下适当减小螺栓扭矩,以便于桥上无缝线路附加力的释放。研究成果对于优化轨道结构设计、验证和完善无缝线路扣件纵向阻力取值计算理论具有参考意义。In order to evaluate the adaptability of the fasteners used for continuous welded rail(CWR)on bridge of high-speed railway to the service environment,taking the WJ-8 type small resistance fasteners as an example,a series of indoor longitudinal resistance tests were carried out.An ambient temperature from-30℃to 60℃and a bolt torque from 90 N∙m to 120 N∙m were set.The loading was carried out at a constant rate of 10 kN/min in the standard assembly state.The longitudinal force value and the longitudinal displacement value of the rail were recorded in real time,and each working condition was loaded 4 times.The tests obtained the longitudinal resistance-displacement variation characteristics of fasteners under 4 different torques and 10 different temperature cross conditions.The mapping relationship among temperature,torque and longitudinal slip resistance have been obtained.The research results are drawn as follows.1)Under different working conditions,the longitudinal resistance of fasteners increases with the increase of displacement in an exponential function.Under the action of different torques,the longitudinal sliding resistance of fasteners increases in exponential function with the increase of temperature.Under the action of different temperatures,the longitudinal sliding resistance of the fastener increases linearly with the increase of torque.2)Both the torque action and the temperature action have an effect on the longitudinal resistance of the small resistance fastener,but the torque action hardly affects the sensitivity of the fastener resistance to temperature changes,and vice versa.3)When the temperature rises to 40℃,under the torque of 90~120 N∙m recommended by the code,the longitudinal sliding resistance no longer meets the requirement of 4±1 kN.It is recommended to appropriately reduce the bolt torque in a high temperature environment,so as to release the additional force of CWR on bridge.4)The research results have reference significance for optimizing track structure design,verifying a

关 键 词：桥上无缝线路 附加力 WJ-8型小阻力扣件 温度 扭矩 纵向阻力 

分 类 号：U213.53[交通运输工程—道路与铁道工程]