Test Model Research On The Important Node Of Van Body Structure

With the rapid development of our social economy, it is a pivotal question to increase the transportion ability. Freight trains are developping to rapid and over loading direction. However, with the railway freight rate and loads increasing, the structure of railway freight has increasingly severe fatigue. There are many truck body fatigue failure with this or that phenomenon. For example, the root of weld side column parts, pillow cover beam web and welded on site, center plates, side wall, the beam connecting plate and the welding position of the crack appear fatigue cracks and so on. Therefore, an accurate understanding of the fatigue properties of trucks, for truck fatigue and safe operation, has important academic significance, economic significance and practical significance.At present, the fatigue study level of rolling stock is far below the one abroad. to the van body structure, we can only do static load test because of the large size and the localization of test equipment,such as the vertical static load test and longitudinal force test.and we can only do fatigue tests of individual components on the truck,or use computer to simulate the virtual fatigue test.To the van body,such large and complex structure fatigue test is not yet possible. Therefore, the main node body fatigue tests is becoming a possible study.In this thesis, with the establishing of beam element model of van body, force analysis on the condition of many instance and the limitation of the practical condition of test, the important node receiving the bigger force is founded. And the result is accord with the reality breakage.That is to say, the basic model of fatigue test model is founded. By the analysis on the old estimate result, and with the equivalent stress distribution principle conditions of basic model are received; afterwards, with the simulating of boundary conditions and equivalent loads and foundation of the assistant structure, the fatigue model of the important node of van body is received, which is close to the reality work conditions. With analysis, discussing and using the knowledge studied, the new method on the theories of numerical analysis and singular function is used to solve the question of equivalent loads simulation.In this thesis, with reference toTB/T1335-1996《strength design of railway vehicles and the identification of standardized test》requirements, beam element model of the body is established by I-DEAS, through The static strength analysis on the truck body of C80B model and through the study on stress and displacement of the truck body, the main node with the bigger force is received, then by simulating the equivalent loads and boundary conditions, and the establishment of secondary structure, the truck body fatigue test model is established.