WJ-7型无砟轨道扣件扣压力损失的室温蠕变试验研究  

Experiment Research on Room Temperature Creep Affecting Clamping Force Loss of WJ-7 type Ballastless Track Fastener

作　　者：伍曾[1,2] 李洁青 黄伟[1] 陶忠[1] 

机构地区：[1]昆明理工大学土木工程学院,昆明650500 [2]西南交通大学高速铁路线路工程教育部重点实验室,成都610031

出　　处：《铁道标准设计》2014年第8期60-63,共4页Railway Standard Design

基　　金：国家自然科学基金青年科学基金项目(51208240);云南省人才培养基金项目(14118469);西南交通大学高速铁路线路工程教育部重点实验室开放研究基金资助课题(2012-HRE-03)

摘　　要：为了探讨室温（常温）蠕变对无砟轨道扣件扣压力损失的影响,通过试验研究分析室温蠕变对WJ-7型扣件扣压力的损失。分别进行保持扣件变形不变与保持初始扣压力不变的2组（各5套扣件）试验,在组装好的扣件相应位置埋设压应力传感器以测量扣件扣压力,在保持一定扣压力情况下,用T形螺栓螺母位移的变化表示弹条的蠕变变形量,对比分析2种情况下扣件蠕变规律及其对扣压力的影响。试验表明：在初始扣压力为10 kN,分别保持扣件弹条变形不变和保持扣件扣压力不变情况下,弹条蠕变分别为1.45 mm和2.12 mm,若都转化成扣压力的损失,则分别为1.00 kN和1.46 kN,且二者蠕变都是前期快后期慢,但后者蠕变时间更长,且蠕变量更大；在无车辆荷载作用下,轨下垫板变形是弹条变形的1/50~1/80,对弹条蠕变变形的影响可以忽略。To ascertain the influence of room temperature creep on the clamping force loss of ballastless track fastener, this paper researched the influence of room temperature creep on WJ-7 type fastener＇s clamping force loss by means of experiment. The experiment for two groups of fasteners （ 5 sets of fasteners for each group ） were respectively carried out, in which the one group retained the constant fastener deformation and the other group retained the constant initial clamping force, while the stress sensors were embedded at the relevant positions of the assembled fasteners so as to measure the clamping forces of the fasteners. Under the circumstance that a certain clamping force was retained, the creep deformation of the spring clip was represented by the displacement change of T-shaped bolts and nuts;and finally, a comparative analysis between the two groups was carried out regarding how the creep deformation of fastener would affect its clamping force. The experiment showed that： when the clamping force was 10 kN and respectively with the constant fastener spring clip＇s deformation and constant fastener＇s clamping force, the creeps of spring clips would respectively be 1. 45 mm and 2. 12 mm; if transforming all them into clamping force loss, there would be 1. 00 kN and 1. 46 kN respectively;moreover, the creep speeds of the both groups were quick in the early stage and slow in the later stage, but the creep time of the latter group was relatively long and with larger creep deformation. In addition, in the absence of vehicle loading, the deformation of rail pad was 1/50 to 1/80 of spring clip＇s deformation, so the effect of the deformation of rail pad on the creep deformation of spring clip could be ignored.

关 键 词：无砟轨道 WJ-7型扣件 蠕变 弹条 扣压力 

分 类 号：U213.5[交通运输工程—道路与铁道工程]