Stress Analysis And Optimal Design Of Rail Joint

The structure,the form and the function of the rail joint is summarized systematically in this paper. At the same time,the defect and disease of rail joint is also introduced. After studying the former static calculation method of rail joint,a new calculation model of joint is presented in the article. The new model is built according to the real size of rail joint by finite element software ANSYS,thus can analyze the stress of all parts of rail joint. With the finite element method,we can not only avoid the complicated boundary condition and theory derivation,but also avoid simplifying the rail joint in new calculation model. Therefore the calculation of rail join is more accurate.As the analysis shows that stress of the outside joint bar of rail is higher than that of the inner joint bar when a wheel rolls over the rail joint. Furthermore the change of bolt tension has great effect to the stress distribution and stress level of all parts of rail joint. As the bolt tension increase,the tension of rail web,stress of joint bar and stress of joint bolt would increase accordingly,but the displacement of rail would become smaller. Commonly,if slide between joint bar and rail is permitted,the bolt torque ranged from 500N-m to 700N-m is suitable. If the joint is "frozen",the bolt torque should range from 900N-m to 1100N-m.In this paper we present improved draft of joint bar in the base of the analysis of rail joint. The draft is reasonable for it can make the stress evenly when a wheel rolls over the rail joint.