Dynamic characteristics of ballast mechanics based on the coupling of discrete element and finite element
                                                     LI Xianzeng, WANG Lihua, CHENG Shuangjiao, XIANG Yongzhi
             （Faculty of Mechanical and Electrical Engineering, Kunming University of Science and Technology, Kunming 650500, China）

Abstract: Aiming at the dynamic characteristics of the ballast bed, the sleep stress and the bed settlement under different axle speeds and train axle weights were studied, the relationship between the average angular velocity variation of the ballast and the bed settlement characteristics under the mesoscopic angle was studied. The finite element and discrete element coupling modeling method was used to establish the orbital track refinement model of sleepertrack bed based on real ballast particle model. The coupling module of EDEM software and ANSYS software were used, the simulation test analysis of the dynamic characteristics of the ballast bed under different driving speeds and train axle weights was carried out, the correlation between ballast settlement and existing experimental data was compared. The results indicate that the numerical model can simulate the real situation better, the driving speed and axle load have a positive correlation with the settlement of the track bed, the driving speed and axle load have a negative correlation with the average angular velocity of the ballast. As the train running speed and axle load increase, the maximum stress value of the sleeper changes accordingly. The greater the contact strength between the sleeper and the track bed, the greater the settlement of the track bed.

Key words: ballastbed; finite element; discrete element; coupling; dynamic characteristics