Vehicle-Bridge Coupling Vibration Analysis Of Rush-repair Girder For High Speed Railway

High-speed railway,as a green and environmental protection,safe and convenient transport method,plays an important role in Chinese transport system.China is the country which has the longest high-speed railway operation length and the largest construction high-speed railway scale across the world.However,China has no specific rush-repairing technology and rush-repairing equipment reserve for high-speed railway bridge and it is urgent to research a required girder part rushrepairing structure for high-speed railway bridge rush-repairing.The research group of this thesis has prompted a high-speed railway girder rush-repairing technological plan which can be transferred to permanent bridge structure in primary stage and has conducted analysis and research toward its mechanical property.In order to further observe the safety and comfort performance when high-speed vehicle passing by the rush-repairing girder and the rush-repairing girder's vibration performance,this thesis,based on finite element software ANSYS and many-body dynamic software SIMPACK,analyzes the vehicle-bridge coupling dynamic response of high-speed railway rush-repairing girder and the main works and conclusions are as follows:The basic theories of multi-body dynamic are introduced and SIMPACK software is employed to establish the multi-body dynamic model of the rail.Meanwhile,the wheel-rail effect relation and rail incentive method are analyzed and the linear critical speed and nolinear critical speed of high-speed vehicle are calculated.Finally,the dynamic judgment indexes of the two independent subsystems-vehicle and bridge are identified.Based on the two kinds working statues,namely temporary operation and normal operation,ANSYS finite element structure analysis technology is employed to establish the dynamic analysis model of rush-repairing girder and the structural analysis and modal analysis are conducted to the rush-repairing girder to gain the natural vibration characteristics of rush-repairing girder.And then,data exchanges ofbridge and vehicle the two subsystems on the dispersed information points of wheel-rail contact surface are conducted so as to realize the vehicle-bridge coupling vibration simulated analysis.The vehicle-bridge coupling analysis results of rush-repairing girder under temporary operation show that: when the vehicle speed is within the range of 10~130km/h,the vehicle safety performance index is within tolerance range,the vehicle comfort degree is “excellent”,the bridge vibration performance is good,and the vehicle speed of temporary operation on rush-repairing girder can be determined as120km/ h which confirms to the expectant vehicle speed.The vehicle-bridge coupling analysis results of rush-repairing girder under normal operation show that: when the vehicle passing by the rush-repairing girder with the speed of 350km/ h,the vehicle safety performance index is within tolerance range and the vehicle comfort degree is “excellent”.Thickening the outside web of rush-repairing girder can effectively increase the transverse rigidity of rush-repairing girder and then decrease the transverse bridge direction dynamic displacement.And the optimized permanent rush-repairing girder structure has about the same vehicle-bridge coupling vibration performance with the original duplet monolithic prestressed concrete box girder and can replace the damaged old girder in normal operation.