梁体温差对桥上无砟轨道横向稳定性影响研究

Study on the Influence of Beam Temperature Difference on the Lateral Stability of Ballastless Track on Bridge

随着桥上无缝线路在运营中出现各种病害,桥上无砟轨道的横向稳定性问题越来越引起重视。基于梁轨相互作用原理,利用有限元方法,建立桥上CRTSⅢ型板式无砟轨道横向稳定性分析模型,分别计算分析梁体在均匀温度和双向温度梯度下对无砟轨道结构横向变形的影响,有益于进一步深入研究桥上无砟轨道的横向变形机理。结果表明:与均匀温度荷载相比,双向温度梯度荷载对无砟轨道结构横向变形影响相对较小,但对钢轨轨距的影响较大,桥上无砟轨道结构的横向稳定性受梁体伸缩附加力与梁体几何形变的共同影响。因此建议在设计桥上无缝线路时,无论考虑哪种梁体温差荷载,都需要对桥上无砟轨道结构的横向稳定性进行检算。

As various problems arise in the operation of CWR on bridge,the lateral stability of ballastless track on bridge has become more and more important. Based on the principle of interaction between beam and rail,the finite element method is used to build the lateral stability analysis model of CRTS Ⅲ slab ballastless track on bridge. The influences of the beam with uniform temperature and bidirectional temperature gradients on the lateral deformation of ballastless track on bridge are calculated,which is beneficial to the further study of transverse deformation mechanism of ballastless track on bridge. The results show that in comparison with the uniform temperature load,the bidirectional temperature gradient load has smaller influence on the lateral deformation of ballastless track,but has greater influence on the gauge; the lateral stability of ballastless track on bridge is influenced jointly by the additional expansion force of girder and beam geometry deformation. Thus,when designing the CWR on bridge,the lateral stability of ballastless track on bridge should be calculated regardless of which beam temperature load is considered..