The damage of the self-compacting concrete in CRTSⅢslab ballastless track on bridge will lead to a partial void of the track slab,which will affect the comfort and safety of the train and the durability of the track ...The damage of the self-compacting concrete in CRTSⅢslab ballastless track on bridge will lead to a partial void of the track slab,which will affect the comfort and safety of the train and the durability of the track slab and bridge structure.In order to study the impact of the interface crack on the dynamic response of CRTSⅢballastless track system on bridge,based on the principle of multi-body dynamics theory and ANSYS+SIMPACK co-simulation,the spatial model of vehicle-track-bridge integration considering the longitudinal stiffness of supports,the track structure and interlayer contact characteristics were established.The dynamic characteristics of the system under different conditions of the width,length and position of the interface crack were analysed,and the limited values of the length and width of the cracks at the track slab edge were proposed.The results show that when the self-compacting concrete does not completely void along the transverse direction of the track slab,the crack has little effect on the dynamic characteristics of the vehicle-track-bridge system.However,when the self-compacting concrete is completely hollowed out along the transverse direction of the track slab,the dynamic amplitudes of the system increase.When the crack length is 1.6 m,the wheel load reduction rate reaches 0.769,which exceeds the limit value and threatens the safety of train operation.The vertical acceleration of the track slab increases by 250.1%,which affects the service life of the track system under the train speed of 200 km/h.展开更多
Wheel/rail rolling contact is a highly nonlinear issue affected by the complicated operating environment(including adhesion conditions and motion attitude of train and track system),which is a fundamental topic for fu...Wheel/rail rolling contact is a highly nonlinear issue affected by the complicated operating environment(including adhesion conditions and motion attitude of train and track system),which is a fundamental topic for further insight into wheel/rail tread wear and rolling contact fatigue(RCF).The rail gauge corner lubrication(RGCL)devices have been installed on the metro outer rail to mitigate its wear on the curved tracks.This paper presents an investigation into the influence ofRGCL on wheel/rail nonHertzian contact and rail surface RCF on the curves through numerical analysis.To this end,a metro vehicle-slab track interaction dynamics model is extended,in which an accurate wheel/rail non-Hertzian contact algorithm is implemented.The influence of RGCL on wheel/rail creep,contact stress and adhesion-slip distributions and fatigue damage of rail surface are evaluated.The simulation results show that RGCL can markedly affect wheel/rail contact on the tight curves.It is further suggested that RGCL can reduce rail surface RCF on tight curves through the wheel/rail low-friction interactions.展开更多
基金Project(2017YFB1201204)supported by National Key R&D Program of China。
文摘The damage of the self-compacting concrete in CRTSⅢslab ballastless track on bridge will lead to a partial void of the track slab,which will affect the comfort and safety of the train and the durability of the track slab and bridge structure.In order to study the impact of the interface crack on the dynamic response of CRTSⅢballastless track system on bridge,based on the principle of multi-body dynamics theory and ANSYS+SIMPACK co-simulation,the spatial model of vehicle-track-bridge integration considering the longitudinal stiffness of supports,the track structure and interlayer contact characteristics were established.The dynamic characteristics of the system under different conditions of the width,length and position of the interface crack were analysed,and the limited values of the length and width of the cracks at the track slab edge were proposed.The results show that when the self-compacting concrete does not completely void along the transverse direction of the track slab,the crack has little effect on the dynamic characteristics of the vehicle-track-bridge system.However,when the self-compacting concrete is completely hollowed out along the transverse direction of the track slab,the dynamic amplitudes of the system increase.When the crack length is 1.6 m,the wheel load reduction rate reaches 0.769,which exceeds the limit value and threatens the safety of train operation.The vertical acceleration of the track slab increases by 250.1%,which affects the service life of the track system under the train speed of 200 km/h.
基金supported by the National Key Research and Development Program of China(Grant No.2020YFA0710902)the National Natural Science Foundation of China(Grant Nos.51735012,52072317,and UJ9A20110)the State Key Laboratory of Traction Power(Grant No.202JTPL-T08).
文摘Wheel/rail rolling contact is a highly nonlinear issue affected by the complicated operating environment(including adhesion conditions and motion attitude of train and track system),which is a fundamental topic for further insight into wheel/rail tread wear and rolling contact fatigue(RCF).The rail gauge corner lubrication(RGCL)devices have been installed on the metro outer rail to mitigate its wear on the curved tracks.This paper presents an investigation into the influence ofRGCL on wheel/rail nonHertzian contact and rail surface RCF on the curves through numerical analysis.To this end,a metro vehicle-slab track interaction dynamics model is extended,in which an accurate wheel/rail non-Hertzian contact algorithm is implemented.The influence of RGCL on wheel/rail creep,contact stress and adhesion-slip distributions and fatigue damage of rail surface are evaluated.The simulation results show that RGCL can markedly affect wheel/rail contact on the tight curves.It is further suggested that RGCL can reduce rail surface RCF on tight curves through the wheel/rail low-friction interactions.
