高速铁路弹性轨枕有砟轨道力学特性试验研究

Experimental study on mechanical characteristics of elastic sleeper ballast track on high-speed railways

根据我国高速铁路设计相关规定,桥上有砟轨道地段应采用弹性轨枕或砟下垫,但目前对其研究较少。基于此,本文进行了系统的高速铁路桥上弹性轨枕有砟道床静、动力学特性试验研究,得出如下主要结论:1采用弹性轨枕后,道床的纵、横向阻力均较普通道床小,但能达到高速铁路有砟轨道的开通要求;2弹性轨枕有砟道床具有较小的支承刚度,能满足高速铁路钢轨支点刚度不大于30k N/mm的要求;3相对于普通道床,采用弹性轨枕后,会显著降低钢轨及桥梁的振动加速度,具有良好的减振、隔振性能;4采用弹性轨枕能有效减小道床的应力,大大减小线路养护维修工作量,体现了良好的优越性,适合于在桥上及岩质路堑等刚性基础地段铺设;5采用弹性轨枕会增大轮轨横向作用力及钢轨、轨枕的横向位移,使列车的运营安全性有所降低。总体上研究认为,在高速铁路桥上采用普通轨枕道床与弹性轨枕道床均能满足高速铁路有砟轨道开通的要求,但在满足高速铁路安全运营的前提下,从减小道砟受力,减少养护维修,提供良好的减振、隔振等方面考虑,建议高速铁路桥上有砟轨道采用弹性轨枕结构。

According to specification of high-speed railways in China,elastic sleeper or ballast mat should be used in ballast track section on bridges. But the current research is relatively rare in the field. Based on this,systematic experimental research is done on the static and dynamic characteristics of elastic sleeper ballast track on high-speed railway bridges. Conclusions are as follows:( 1) Although the longitudinal and lateral resistance of ballast bed is smaller than conventional ballast bed after elastic sleeper is used,the values can still meet the requirements of high-speed railway ballast track.( 2) Elastic sleeper ballast track has smaller support stiffness,which can meet the requirements that rail support stiffness should be no more than 30 k N / mm in high-speed railways.( 3) The vibration accelerations of rail and bridge are signally smaller when elastic sleeper is used,which shows that elastic sleeper ballast bed has good damping performance.( 4) Stress in elastic sleeper ballast bed is much smaller than that in conventional ballast bed,leading to less maintenance and repair of railway lines,which shows its superiority in the application in rigid foundation section such as bridge and rock cutting.( 5) The wheel / rail lateral force and lateral displacements of rail and sleeper will increase when elastic sleeper is used,reducing the operation safety. In overall,conventional sleeper ballast bed and elastic sleeper ballast bed both meet the requirements of high-speed railways. But taking into account the aspects of reducing the stress of ballast,less maintenance and repair,good damping performance,the elastic sleeper ballast bed is proposed to be used on high-speed railway bridges.