The Analysis Of High-speed Rail Frame Structure And Fatigue Strength Evaluation

The so-called fatigue strength is the biggest stress that metal materials can bear times without breaking. In fact, metal materials cannot bear cyclic stress Infinitely many times. About more than 80% of the mechanical parts failure belongs to fatigue failure. And there is no obvious deformation before fatigue damage occurs. So fatigue strength often cause major accidents. So the study of the influence factors of fatigue strength is very necessary.In this paper, In this paper, through theoretical research combined with experiment method. There are three factors which affect fatigue stress:stress concentration, size effect and surface finish. They all influence each other, The paper come up with a comprehensive correction coefficient factor. Also, there is the stress analysis of high speed rail structure and testing scheme and data processing in detail in this paper. In this paper, the research content includes:(1) This paper studies the stress concentration, size effect and surface finish. There is a deep discussion of the co-factors of size effect and stress concentration, and the co-factors of stress concentration and surface finish. The paper uses experimental data to verify the practicability of the comprehensive influence coefficient factors.(2) Through the study of the finite element analysis of L-shaped sample, calculate the L-shaped sample gap position of maximum stress, and through the processing of experimental data, calculate the 1-shaped specimen fatigue stress.(3) Through the chute floor modeling calculation, it is necessary for specific forms and characteristics of structure, the finite element analysis was carried out on the structure, determine the test pieces of the constraints of the form loading position, ensure the test structure deformation and high stress points and the actual situation as consistent as possible. In addition, determining the test load level and the number and location of test points.