East China Jiaotong University
In order to analyze the effect of the number of empty trains on the safety of freight trains, a dynamic model of the Train-Track coupling system with empty vehicles and heavy vehicles was established based on the theory of vehicle system dynamics, train longitudinal dynamics theory and the theory of Vehicle-Track coupling dynamics. Based on this, the lateral wheelset force, the derailment coefficient, the wheel unloading rate was analyzed when different numbers of empty vehicles were located in the head and rear parts of the freight train while braking. The results show that when 5, 10, and 20 empty vehicles were marshalling at the head and tail of the train, the lateral wheelset force, the derailment coefficient, the wheel unloading rate of the empty and heavy vehicles all meet the standard requirements of the GB/T 5599-2019 standard and have a certain safety margin. When the empty and heavy vehicles mixed marshalling train braking on curve railway, the lateral wheelset force of the empty vehicle is less than that of the heavy vehicle, and the derailment coefficient and wheel unloading rate of the empty vehicle are greater than that of the heavy vehicle. When 5 empty vehicles were located at the head and tail of the train, the lateral wheelset force of the empty vehicle and the heavy vehicle are all the smallest, but the wheel unloading rate of the empty vehicle at the tail is the largest at the same time. For the derailment coefficient and wheel unloading rate, except for the case of only 5 empty vehicles located in the head and rear marshalling, the derailment coefficient and wheel unloading rate of the empty vehicles marshalling at the head of the train are larger than those of the tail empty vehicles. When the head and tail of the train are marshalling of 10 and 20 empty vehicles respectively, the difference in the overall wheel load reduction rate of the two trains is small.