Adaptability Improvement Of Existing Heavy-Haul Railway Bridges To Axle Load

The research and engineering practice abroad show that the increase of the axle load of freight cars can effectively the railway transportation capacity. Some countries developed heavy-haul transportation have been develop the heavy-haul transportation by means of the improvement of the existing railway line strength, establish of the preventive maintenance system and the perfect management of wheel/rail and so on. The axle load of the heavy-haul train which runs on the Da-Qing railway and Shuo-Huang railway is21t-25t, the heavy-haul railway transportation has the greater annual amount of shipping and the train density, although there is great disparity in the maintenance and axle load of freight cars compared to the heavy-haul railway. The increase of the axle load will bring new challenges for the railway bridge restricts the development of the existing heavy-haul railway to the increase of the axle load of freight cars. The Shuo-Huang railway is taken as an example, based on the heavy-haul train-ballast track-bridge system, the following innovative research work is done in this paper.(1) Bogies are bolster and side frame3-D vibration model of the train including the car body, bolster, side frame and wheel-set is established, the bogie is regarded as the whole body which characterize the heavy-haul freight cars; sleeper and ballast bed are regarded as the rigid Euler beam, the ballast is simulated as the uniform linear spring and dashpot system, the model of the three-layer ballast including rail, sleeper and ballast bed is set up; the interaction between the rail and bridge is discrete to the uniform linear spring and dashpot system, the track irregularity is considering, the analysis model and method of the heavy-haul train-ballast track-bridge coupling system are established. (2) Based on the dynamic analysis theory of heavy-haul railway bridge, a computer program for the heavy-haul train-ballast track-bridge coupling system is developed by the MATLAB and ANSYS software, The Shuo-Huang railway is taken as an example, the field on heavy-haul railway bridge the trains is carried out, the test results are compared with the analysis results to verify the reliability of the theory method and simulation software.(3) The on-line monitoring system on heavy-haul railway bridge on the service state is developed system include the sensor system, data acquisition system, data management system, data collecting and processing system and failure self-diagnosis and alarm on system real-time dynamic behavior of the heavy-haul railway bridge can be by the broadcast wireless internet the index of bridge exceed the limited value, the automatic alarm control system will be started.(4) Based on the existing research, the service state evaluating indexes of the heavy-hual railway bridge is determined Wentang river bridge is taken for an example to evaluate the service state of the bridge and analyze the adaptability of the axle load of the bridge the theory analysis, online monitoring results and the test results.(5) The three reinforcement scheme the auxiliary steel beam, the discrete girder external steel-concrete composite roof truss and the self-balancing external under the axle load28t-40t, the suitable axle load and running speed of the heavy-haul railway train are on the theory and the results.