A Bridge Weigh-in-Motion(BWIM) Method For High Speed Railway Vehicle Considering Vehicle-Bridge Coupling Effect

With the rapid development of high-speed railway,Chinese railway transportation is developing towards high-speed and heavy load.For railway trains,accurate weight information is of great value to the evaluation and maintenance of railway infrastructure.However,Existing bridge weigh-in-motion(BWIM)methods can introduce errors when the vehicle speed is high so that the dynamic effect cannot be filtered by signal processing.Therefore,this paper proposes a new BWIM algorithm(SPKF algorithm)for fast-moving railway train based on the dynamic coupling of vehicle bridge system.This paper focuses on the following aspects:1.The theoretical principle and numerical realization process of traditional bridge weigh-in-motion method as well as its essential defects and limitations are systematically analyzed.Traditional BWIM methods assume that dynamic effects are additional fluctuations around static responses that can be filtered by using signal processing methods.However,with the increase of the vehicle speed,the dynamic interaction duration between the vehicle and the bridge becomes shorter,resulting in transient signals that makes it difficult to filter the dynamic effect.2.Based on the vehicle bridge coupling system,a fast bridge weigh-in-motion algorithm for high-speed railway passenger vehicle is proposed.Firstly,the vertical coupling motion equation of railway passenger vehicle-bridge is established,and the state-space model of the vehicle-bridge system is formed.Then,taking part of the bridge dynamic response generated by the railway passenger vehicle crossing the bridge as the observation data,it is input into the SPKF algorithm to estimate the weight and other information of the railway passenger vehicle.The effectiveness of the algorithm is verified by example analysis,and the algorithm has high recognition accuracy,fast convergence speed,good stability and strong anti noise performance.3.Based on the vehicle bridge coupling system,a fast bridge weigh-in-motion algorithm for railway freight vehicle is proposed.Firstly,the coupled motion equation of railway freight vehicle-bridge is established,and the time-varying vehicle-bridge state space equation is formed;Then,the weight identification of railway freight vehicle is transformed into the parameter identification of vehicle bridge system,and the state space model of vehicle bridge system is established.Finally,SPKF algorithm is used to analyze the dynamic weighing of railway freight vehicle.The effectiveness of the algorithm is verified by example analysis,and the algorithm has high recognition accuracy,good stability and strong anti noise performance.4.Considering the actual situation,the proposed algorithm is further verified in the case of parameter uncertainty.The influence of the uncertainty of vehicle(stiffness k and damping c)and bridge parameters(elastic modulus E_b and mass density m_b)on the recognition of train weight by SPKF algorithm is studied respectively.The research shows that as the results are largely affected by the accuracy of the estimated E_b,to ensure the accuracy of the weight identification,the stiffness of the bridge needs to be identified with field tests.