Residual Life Prediction And Reinforcing Analysis For The Corbel Of CRH2046

Corbel is one of the main bearing parts of the CRH2046.Used in engineering under the impact of great tension,compression and alternating load,its main failure form is fracture.With the promotion of speed,the using condition of corbel has become increasingly strict and crack failure has also rises,resulting in crack failure problem,which become hidden danger to the safety in the running of the train.So in this paper we mainly study the residual life and the reinforcement of the corbel structure,the residual life prediction method and calculation procedure of the corbel structure is summed up based on the fracture mechanics.First of all,according to the standards,bolster and swing sets of TB-T2637-2008 railway passenger train,the load size and case of vertical direction,longitudinal direction and transverse direction in corbel running process are obtained.Then,the static strength finite element analysis of each load is used to obtain the stress at the position that actual beam structure appears after corbel service.The results of the maximum principal stress in several groups of working case are chosen as the basis for future calculation.Secondly,a three-dimensional simplified model equivalent to the whole model is obtained according to sub-model technology.The finite element software workbench is used to create crack in the position that actual crack appears of sub-model.The stress intensity factor of the position is obtained,and then the value of the shape factor of the stress intensity factor is calculated.Using the MATLAB software,the fitting formula of the shape factor and the stress intensity factor of the stress intensity factor is obtained,which lays the foundation for the prediction of the remaining life.Thirdly,the structure of corbel after service is reinforced in order to ensure the safe operation of EMU and improve the residual life of the corbel structure.According to"Regulations of the railway vehicle structure maintenance and equipment",several groups of reinforcement plan were obtained.Through the static analysis of corbel,stress value and stress distribution is observed in dangerous position after reinforcement.According to the value of equivalent stress and the stress intensity factor,the optimal reinforcement plan is obtained.Fourthly,the crack is created in the same position of corbel after reinforcement.By analysis,the fitting formula of the shape factor and the stress intensity factor after reinforcement is obtained.Finally,the initial crack length is regarded as a variable to calculation the residual life of corbel before and after reinforcement.By using MATLAB to fit the data,the relationship between the residual life and initial crack length is obtained.