重载铁路隧道内弹性支承块式无砟轨道结构优化研究

Structural Optimization of Elastic Supported Block Ballastless Track in Heavy-Haul Railway Tunnels

为解决现有弹性支承块式无砟轨道动态轨距变化量大、轨道几何形位的保持能力相对较弱的问题,提出一种斜坡型弹性支承块式无砟轨道。采用静力计算方法,通过分析钢轨和支承块变形、支承块相对支承块槽的位移以及支承块和道床板的受力状态,研究弹性支承块短侧面的合理坡度;基于模拟落轴试验,研究斜坡型弹性支承块式无砟轨道部件刚度匹配问题。研究表明:斜坡型弹性支承块对于控制轨道结构变形,改善支承块、橡胶套靴及道床板等轨道结构受力状态更加有利。建议在30 t轴重条件下,弹性支承块短侧面坡度取1∶5~1∶6,套靴刚度取200 kN/mm左右,块下垫板刚度取80 kN/mm左右较为合理。

The elastic supported block ballastless track has several disadvantages,such as major dynamic gauge variation and moderately weak track geometry retention capacity.Hence,a slope elastic supported block ballastless track is proposed.The rail and support block deformation,the support block displacement relative to the support block groove,and the support block and track bedplate stress state are analyzed using the static calculation method to estimate the reasonable slope of the short side of the elastic support block.Based on the simulated axle drop test,the stiffness matching of components of a slope elastic supported block ballastless track is further examined.The results show that the slope elastic support block is better for controlling the track structure deformation and improving the stress state,such as support block,rubber boots,and track bedplate.It is proposed that,when the axle load is less than 30 tons,the slope value of the short side of the elastic support block should be 1∶5 to 1∶6,the boot stiffness should be approximately 200 kN/mm,and the stiffness of the bedplate under the block should be approximately 80 kN/mm.