Finite Element Analysis On Bus Body Frame Break

Body is the important part of big and medium-sized passenger bus. Many body frame components of road traveling bus produced in Yaxing coach Ltd., occurred early failure only after about 70,000--80,000 km driving. The early failure would affect passengers'safety and proprietors'benefit. FEM (Finite Element Method) is an advanced modern design analysis method. It can be effectively used in bus body frame strength early failure analysis. Using Ansys software, this thesis analyzed the body frame strength early failure, and found the reason, which caused the body frame early failure problem. The main research contents are as follows:1. This thesis first comprehensively introduced the domestic and international present state and the development trend of the FEM in the city bud design. It elaborated the application of FEM in the strength analysis of the bus body frame. Starting using FEM on a large scale in the passenger car industry is relatively late in China. Fortunately, the enterprises realized its importance and made some effort on the FEA(finite element analysis) of the structure of bus. This thesis expatiated on the research significance and necessities of this project.2. According to the requirement of the research project, and based on the elaboration of the typical road traveling bus structure, the thesis analyzed the characters of road traveling bus body frame component and the early failure of the bus, which has occurred only after about 70,000--80,000 km driving. We also proposed the method to solve the early failure problem.3. It generalized the application of bus body theoretic, finite element theoretic and computation, Ansys software. Based on these, several modeling method of bus body frame nowadays by using FEM were studied, and the characteristic of beam unit modeling and shell unit modeling as well as the advantage and the disadvantage of them were analyzed. Beam unit modeling has the advantages of little workload and put forward computation result very soon in the stage of pattern...