铁道科学与工程学报2025，Vol.22Issue(5)：2114-2125,12.DOI:10.19713/j.cnki.43-1423/u.T20241183
轨下垫板窜出对扣件纵向阻力的影响研究——以WJ-8型小阻力扣件为例
Influence of sliding pad on longitudinal resistance of fasteners by taking WJ-8 fastener as an instance
摘要
Abstract
The continuously welded rail track on the long-span continuous bridge is subject to additional forces such as temperature and braking forces,resulting in frequent relative displacements between the beam and the track.This leads to the pad of the fasteners at the beam ends sliding.In order to study the influence of sliding pad on longitudinal resistance of fasteners,taking WJ-8 type small resistance fastener as an instance,the paper analyzed the fasteners state during pad slide.The influence factors were mainly reflected in the reduction of the force area of pad and the compression of the pad shoulder by rail and iron pad.Accordingly,indoor tests were conducted to measure the longitudinal resistance of rail fasteners with and without pad shoulder under different torques and different pad sliding displacement.By removing the shoulder from the pad,the impact of the reduced contact area on the longitudinal resistance of the fasteners was studied.These results were then compared with tests on standard fasteners with shoulder pad to investigate the effect of shoulder compression on the longitudinal resistance of the fasteners.Experimental results are drawn as follows.(1)For fasteners without pad shoulders,the reduction in force area of the pad leads to a decrease in sliding resistance of the fastener by 2.7%～5.6%,with a relatively minor impact on the longitudinal sliding curve of the fastener.(2)Compression of the pad shoulder significantly alters the longitudinal sliding characteristic curve and sliding point of the rail.After the pad shoulder is compressed stably,it increases the sliding resistance of the fastener by approximately 24.9%～40.3%.(3)With different pad sliding displacements,the longitudinal resistance of fasteners with shoulder pads is significantly greater than that of fasteners without shoulder pads.After the compression of the shoulder pads stabilizes,the longitudinal resistance of the former is 1.29～1.36 times that of the latter.(4)The power exponential function is fitted for the longitudinal resistance-displacement curve of fasteners with pad shoulders at different torques and different pad sliding displacement.In order to make the slip resistance of the small resistance fasteners meet the usage requirement of(4±1)kN,the fasteners should be recovered or replaced in time when the pad is found to have slid more than 15 mm.The research results can provide reference for the state prediction and maintenance of continuous welded rail.关键词
扣件系统/纵向阻力/垫板窜出/WJ-8型小阻力扣件/无缝线路Key words
fastening system/longitudinal resistance/sliding of pad/WJ-8 small resistance fastener/continuous welded rail分类
交通工程引用本文复制引用
曾志平,刘卓,李沛成,王卫东,张志鹏,黄志斌,段廷发..轨下垫板窜出对扣件纵向阻力的影响研究——以WJ-8型小阻力扣件为例[J].铁道科学与工程学报,2025,22(5):2114-2125,12.基金项目
中国铁路南昌局集团有限公司科技研究开发计划课题(202007) （202007）
