重载铁路WJ⁃12型扣件TPEE垫板结构优化设计

Structural Optimization Design of TPEE Base Plate with WJ⁃12 Fastener for Heavy Haul Railway

为解决重载铁路WJ-12型扣件弹性垫板压溃、疲劳后扣件静刚度变化率超限、混凝土轨枕承轨面磨损等问题,对现有热塑性聚酯弹性体(Thermoplastic Polyester Elastomer,TPEE)垫板进行结构优化设计。优化后,TPEE垫板的厚度和面内尺寸保持不变,单个凸台面积增大。采用有限元软件建立TPEE垫板静刚度计算模型和钢轨-TPEE垫板-轨枕耦合模型,对优化前后TPEE垫板的静刚度和TPEE垫板与轨枕的耦合应力进行计算,并通过室内试验对比优化前后TPEE垫板及扣件的静刚度和300万次疲劳试验后的静刚度变化率。结果表明:优化后,TPEE垫板静刚度为47.3 kN/mm,疲劳试验后的TPEE垫板和扣件静刚度变化率均小于20%,满足规范要求;优化后TPEE垫板和轨枕表面受力更为分散、合理,二者相互作用减小。

In order to solve the problems such as collapse of WJ-12 fastener elastic base plate of heavy haul railway,over limit of fastener static stiffness change rate after fatigue,wear of concrete rail sleeper bearing surface and so on,the existing thermoplastic polyester elastomer(TPEE)base plate was optimized.After optimization,the thickness and in-plane dimension of TPEE base plate remained unchanged,and the area of a single boss increased.The static stiffness calculation model of TPEE base plate and the rail-TPEE base plate-sleeper coupling model were established by finite element software.The static stiffness of TPEE base plate and the coupling stress between TPEE base plate and sleeper before and after optimization were calculated,and the static stiffness of TPEE base plate and fastener before and after optimization and the static stiffness change rate after 3 million fatigue tests were compared through indoor tests.The results show that the static stiffness of TPEE base plate after optimization is 47.3 kN/mm,and the change rate of static stiffness of TPEE base plate and fastener after fatigue test is less than 20%,which meets the requirements of the specification.After optimization,the stress on TPEE base plate and sleeper surface is more dispersed and reasonable,and the interaction between them is reduced.