Abstract：In order to analyze the effects of ballast mats on mechanical characteristics of railway ballast bed, the discrete element (DE) method and image processing technique were used to establish the computational model of ballast particles. An elastic bar was used to simulate a ballast mat, and the DE model of a ballast bed with ballast mats was built. The correctness of the model was verified with field test results. Dynamic responses of a conventional ballast bed and those of a ballast bed with ballast mats under action of train load were contrastively analyzed. Results showed that laying ballast mats can reduce the overall vibration level of ballast bed and reduce the average value of vibration acceleration of ballast particles by 9.40%. Laying ballast mats can reduce the number of strong keys in ballast bed, increase the occurrence probability of smaller contact forces in ballast bed, and reduce the average normal contact force of ballast particles by 21.7% and the average tangential force by 24.4%. Ballast mats can significantly increase the number of contact points between ballast particles and lower base, increase contact area, and reduce contact forces. Ballast mats are helpful to reduce the stiffness of ballast bed and increase the elasticity of ballast track.
崔旭浩,肖宏. 道砟垫有砟道床力学特性离散元分析[J]. 振动与冲击, 2020, 39(19): 141-148.
CUI Xuhao, XIAO Hong. DE analysis for mechanical characteristics of ballast bed with ballast mats. JOURNAL OF VIBRATION AND SHOCK, 2020, 39(19): 141-148.
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