Static Mechanical Properties Of Elastic Strip Type ? Fastening System

The main function of rail fastening system is to keep the space position of rail.With the rapid development of railway,there are different degrees of damage in the process of fastening system.The damage of fastener system has a great influence on the safety and stability of driving.Frequent replacement and repair of fastener systems will result in significant economic losses.Therefore,it is necessary to study the mechanical properties of the fastening system.In this paper,the mechanical properties of the elastic strip ? fastening system are studied.an experimental system was developed to test the mechanical properties of the fastening system.The mechanical properties of the single joint fastening system are studied by experiments.The influence of the installation torque,lateral force level and rail pad stiffness on the lateral displacement of rail,the axial force of the bolt,the strain of the elastic bar and the contact stress of the rubber pad under rail are analyzed.According to the actual stress environment of the fastening system,the finite element model of the multi node rail fastening system is established.The influence of the installation torque,transverse force level and the rigidity of the rail pad stiffness on the lateral displacement of the rail,the axial force of the anchor bolt,the elastic strain and the contact stress of the rubber pad under the action of the multi node fastening system are analyzed.The main conclusions are as follows:(1)When the lateral force of the curve section is large,increasing the installation torque can not significantly reduce the lateral displacement of the rail.When the torque is 130 N·m,the lateral displacement of rail can be controlled effectively,At the moment,the internal force of the bolt in the fastener is the smallest.When the installation torque is greater than 140 N·m,The lateral displacement of rail can not be controlled effectively.When the torque is greater than 120 N·m and the lateral force is large,the maximum strain of Spring bar increases rapidly.When the lateral force is large,the contact stress concentration of the outer side of the rubber pad is obvious,and the mounting torque can not change the phenomenon.(2)The effect of multi node fastener system on the mechanical properties of fastener system is considered.The following results can be obtained: When the lateral force is large,the transverse displacement of the rail is larger,and the larger the torque,the smaller the lateral displacement of the rail.When the torque is 140 N·m the change of the axial force of the inner bolt is minimum.When the transverse force is large,under the mounting torque the contact stress of the rubber pad is more uniform,but the stress concentration of the outside of the rubber pad is not changed.Large lateral force and mounting torque are easy to damage the elastic bar.(3)The greater the stiffness of the rail pad,the smaller the transverse displacement of the rail,the smaller the change of the axial force of the bolt.When the transverse force is large,the greater the stiffness of the rail pad,the more obvious the contact stress concentration.When the elastic strip is installed,the stiffness of the rubber pad has a great influence on the stress of the elastic strip.When the elastic bar is working,the stiffness of the rubber pad has little influence on the force.