Research On Structure Analysis Method Of Railway Heavy-haul Wagon

Railway heavy haul transport is the main technological way to improve the transport capacity of large cargoes. And increasing the axle-weight of vehicle and improving the load of vehicle are important measures to develop the railway heavy haul transport. On the premise that the structure strength and stiffness of vehicle meet the requirements, it is a primary issue that the weight of vehicle structure has to be reduced.This paper focused on the research of the body structure of heavy load gondola car which holds the heaviest axle load that is 40 tons, the least self-weight coefficient that is 0.16, the speed coupling of shunting vehicles which is less than 9.5km/h and withstands the longitudinal impact load of 5560kN. A set of nonlinear analysis of railway vehicle was systematically proposed. Numerical simulation system about impact of multi-vehicle coupling shunting was developed. Impact is one of the important causes which lead to the damages of vehicles. Aims at the safety coupling speed of shunting vehicles of heavy haul freight cars, the impedance curve about coupler buffer which was gotten from the shunting impact tests was presented. Numerical simulation programs about impact of multi-vehicle coupling shunting were developed on the platform of ADAMS based on the multi-body system dynamics theory. Dynamic impact characteristics of three different kinds of shunting operations that was one segment vehicle to one segment, two segment vehicle to two and three segment vehicle to three were studied under different shunting impact speeds conditions that were all above 5km/h. The quantitative results were obtained, which can describe the influence coupler buffer capacity with the size of the impact kinetic energy dissipation. And the safety coupling speed of shunting vehicles of heavy haul freight car was proposed.In addition, a series of nonlinear analysis methods for heavy haul freight cars and geometric structures were presented. As for the heavy vehicles, not only the axle-weight should be improved, but also the deadweight should be lightened and the load should be increased to improve their performances. However, the traditional linear elastic structure design methods for Chinese railway vehicles can't meet the demands. Based on the previous results, the further analysis of the nonlinear structure has to be done. The structure of the heavy haul freight car is designed on the principles that the structure is stable and local plastic deformation is allowed. With the utilization of the material hardening property, the local plastic deformation of the structure was allowable and its expansion was controlled to enhance the whole bearing capacity. The impact strength of body structure was analyzed based on the material nonlinear theory. The buckling analysis on the thin-walled whole bearing body structure, which was the combination of plate and beam, was carried out based on the geometric nonlinear theory. From the analysis results, the adjustment and optimization measures of body structure strength and stiffness were proposed. And the body structural optimal design of heavy load gondola car, of which axle load was 40 tons, body structure weight was 8.36 tons and material was Q450NQR1, was done. The products have been put into general production and practical application, which show that the nonlinear structural analysis method is an effective way of the structural optimal design of heavy vehicle.For the flow large-deformation characteristics of bulk goods under the longitudinal impact, using Lagrange_Euler method to describe the bulk goods'motion, the dynamic strength analysis method of body structure under the longitudinal impact was proposed firstly. It consists of the description of ALE Equations of bulk goods, the description of Lagrangian Equations of body structure, the establish of fluid and solid coupled mechanics model and the solving equations for ALE separation technology with the combination of central difference explicit time integration method, Lagrange and Euler algorithm. The dynamic strength analysis method of body structure under the longitudinal impact of different speeds was carried out to obtain the movement characteristics of bulk goods and the dynamic response of the body structure. The problem of the bulk goods flowing out in impact process and how to compute the wall pressure of impact side were solved. Railway heavy haul wagon body of low resistance, lightweight of structure and material was designed. The flat outside sidewall surface with the inner sidewall post can reduce the train running resistances. Besides, the new stainless steel comprised of NIROSTA(?)4003 materials with corrosion resistance was used to manufacture the parts that are with the ore directly. This optimization can further reduce the deadweight and maintenance cost. Based on the private software of car structure lightweight, the study on how to lighten the body structure of gondola car was finished which makes the deadweight of body structure of stainless Steel wagon of 40t axle and 138 tons load is only 7.02 tons.