WJ-8型小阻力扣件轨下胶垫滑出纵向阻力试验研究

Experiment of longitudinal resistance of WJ-8 type small resistance fastener with the sliding of rubber pad

大跨桥梁端处的小阻力扣件轨下橡胶胶垫滑出现象较为普遍,为确定轨下胶垫滑出后扣件纵向阻力值及其变化规律,以客运专线无砟轨道常用的WJ-8扣件为例,开展不同轨下胶垫滑出量条件下的扣件纵向阻力试验,测试5种不同轨下胶垫滑出量时扣件纵向阻力—位移关系;采用最小二乘法对试验数据进行曲线拟合,得出5种不同轨下胶垫滑出量时扣件纵向阻力双线性表达式。研究结果表明:随着轨下胶垫滑出量的增加,扣件纵向阻力值减小,胶垫滑出量在60 mm以内时,扣件纵向阻力受胶垫滑出量影响明显,当胶垫滑出量大于60 mm后,扣件纵向阻力变化不大。

The small resistance fasteners’rubber pads slide a lot on the end of span bridges.In order to deter-mine the longitudinal resistance value and its change of small resistance fastener with the sliding of rubber pad, this paper took the WJ -8 type small resistance fasteners commonly used in ballastless track for example.A ex-periment of testing the longitudinal resistance of WJ -8 type small resistance fastener was designed,and so as to get relationship between longitudinal resistance value and displacement of WJ -8 type small resistance fastener with five kinds of different amounts of sliding of the rubber pad.The curve is fitted by the least squares method, in order to get the bilinear resistance model with the different sliding of rubber pad.The results show that：with the increasing amount of sliding of the rubber pad,longitudinal resistance value of WJ -8 type small resistance fastener decreases,while the sliding is within 60 mm.The sliding has great influence on the longitudinal resist-ance,and when the sliding without 60 mm,the sliding has little influence on the longitudinal resistance.