轮轨振动与气动荷载耦合作用下轻质装配式明洞动力学特性

Dynamic Characteristics of Lightweight Prefabricated Open Cut Tunnel Under Coupling Action of Wheel Rail Vibration and Aerodynamic Load

根据铁路隧道洞口地形特征,设计了一种轻质装配式明洞,采用有限元软件建立了列车轮轨振动与气动荷载耦合模型,分析了高速列车通过时明洞结构响应情况。结果表明:随着接长明洞长度的增加,明洞应力、动变形和振动加速度均减小;在接长明洞长度小于50 m时明洞应力、动变形、振动加速度降速较大。随着距轨面高度的增加,明洞结构的应力和动变形增大,距轨面高度大于6.5 m后应力和动变形的增速变大。列车交会位置对明洞应力和动变形有影响,对振动加速度影响不大。在轮轨振动与气动荷载耦合作用下,明洞应力、动变形及振动加速度均较小,结构处于安全状态。

Based on the terrain characteristics of railway tunnel openings,a lightweight prefabricated open cut tunnel was proposed.A coupled model of wheel rail vibration and aerodynamic load of high-speed train was established by finite element software,and the structural response of the open cut tunnel during high-speed train passage was analyzed.The results show that,with the increase of the extension length of open cut tunnel,the stress,dynamic deformation,and vibration acceleration of open cut tunnel structure decrease,especially when the extension length is less than 50 m.As the height from the rail surface increases,the stress and dynamic deformation of the open cut tunnel structure increase,especially when the height from the rail surface is more than 6.5 m.The intersection position of trains has an impact on the stress and deformation of open cut tunnel,but has little effect on the vibration acceleration.Under the coupling effect of wheel rail vibration and aerodynamic load of high-speed train,the stress,dynamic deformation and vibration acceleration of open cut tunnel are relatively small,and the structure is in a safe state.