高速铁路钢轨焊接接头磨耗演变规律仿真研究OA

During the rapid development of high-speed rail,the non-uniform wear of rail welded joints caused by transient wheel-rail impact is a critical issue that constrains the service life of rails and affects the train safety.To study the wear evolution law of rail welded joints,the ABAQUS-Universal Mechanism(UM)-MATLAB co-simulation technology was adopted.Based on the Kik-Piotrowski wheel-rail contact theory and the Archard wear theory,a wear evolution prediction model of welded joints considering the hardness distribution of the rail was developed.The wear behavior of rail welded joints during long-term service was simulated.The effects of factors such as arrangement positions of rail welded joints,initial irregularities and hardness differences between the heat-affected zone and the rail base material on the wear of rail welded joints were systematically analyzed.The results show that,when the high-speed train passes over rail welded joints,the profile of long-wavelength welded joints can undergoe significant changes.The irregularities phenomenon spreads along the direction of train movement,and the wheel-rail interaction force can exhibit a trend of first decreasing and later increasing in the initial stage of wear.The convex-shaped rail welded joints can cause the reaction of wheel-rail contact forces,and as the train's cumulative passing gross load increases,these lead to periodic irregularities and thus form rail corrugation.Optimizing the position of rail welded joints can reduce wheel-rail impact.When the welded joint is located directly above the rail support,it will result in a larger wheel-rail force compared to that when it is located in the middle of the rail support.Moreover,when the train's passing gross load increases to 30 Mt,the wheel-rail contact force will exceed the safety limit of 170 kN.Controlling the wavelength of the initial welded joint≥0.2 m,the wave depth<0.3 mm,and reducing the hardness differences between the heat-affected zone and the rail base material can effectively delay the wear of convex-shaped welded joints.These findings can provide a theoretical support for the wear assessment and performance optimization of rail welded joints in high-speed rails.