隧道内无砟轨道道床板更换为钢支墩可行性研究

在实际运营中,隧道内轨道结构由于地下水压力作用和混凝土强度不足等问题,出现道床板上拱并产生裂纹病害,当上拱和裂纹达到一定程度,会对行车造成一定的影响,故针对隧道内轨道结构病害提出采用钢支墩更换无砟轨道道床板的整治方案,并提出施工流程建议。此方案结构较为简单,施工更换方便,能够节省施工时间,为快速恢复既有线铁路运营提供了保障。同时基于连续弹性支承梁模型和弹性点支承梁模型,推导出钢轨竖向和横向支点力,将其施加在局部计算模型上进一步开展了力学仿真计算。计算结果表明:钢支墩的埋深比应取1.8,当其出露高度在0.04~0.34 m时,钢支墩周围混凝土的应力及变形均满足设计要求,采用钢支墩更换隧道内无砟轨道方案是可行的。

Feasibility Study on Replacing Ballastless Track Bed Slab with Steel Buttress in Tunnel

In actual operation,upper arches and cracks may appear in the ballastless track bed slab due to insufficient groundwater pressure and concrete strength in the tunnel track structure.When the upper arch and crack reach a certain level,it will have a certain impact on the train driving.For the track structure damage in the tunnel,a remediation scheme for replacing the ballastless track bed slab with steel buttress is proposed.It is time-saving due to its relatively simple structure,convenient construction and replacement,and it provides a guarantee for the rapid recovery of existing railway line operations.Meanwhile,based on the continuous elastic supporting beam model and the elastic point supporting beam model,the vertical and lateral support forces of the rail are derived and applied to the local calculation model for further mechanical simulating calculation It turns out that the buried depth ratio of the steel buttress should be 1.8.When the exposed height is 0.04~0.34 m,the stress and deformation of the concrete around the steel buttress meet the design requirements,indicating that the scheme for replacing the ballastless track bed slab with steel buttress is feasible.