Inhalt

The mechanical behaviors of ballast track is influenced by the form distribution of ballast stones. A reasonable design will greatly improve the mechanical behavior, and thus reduce the maintenance cost of ballast track. This dissertation focuses on proposing optimized ballast stones in regard to their geometrical forms. First, a ballast random form generator is proposed. Afterwards, Discrete Element Method (DEM) based simulations are performed. The simulation model is established based on a box test, whose result is presented. Establishment and calibration process of the model are expatiated. Using the validated parameters and the generated form databases, DEM simulation models with different form distributions of ballast stones in the ballast aggregate are proposed. Based on the results, the form effect on mechanical behavior of the ballast aggregates are studied. The optimized ballast aggregate is proposed based on the findings stated above. The proposed optimized ballast aggregate is expected to be a reference for construction of ballast track in real world. The modeling technic and the calibrated modeling parameters can be used for optimization for different railway operating programs.