朔黄重载铁路移动闭塞信号显示研究

针对C3、CBTC模式存在的地面信号亮红灯(或灭灯)与ATP命令不一致问题,提出新的显示绿闪及点灯电路,解释其含义。分析重载移动闭塞CBTC模式转为LKJ模式影响行车安全的因素,给出重载移动闭塞系统可靠性拓扑图,计算出常态开灯与常态灭灯CBTC系统的可靠性值,得出常态开灯比常态灭灯可靠性高。     

大轴重条件下重载铁路路基变形特性研究

随着重载铁路列车轴重的不断增加,作用于路基上动应力也随之增大,进而引起路基塑性变形和弹性变形的增大,严重影响了列车的安全运行。通过对路基现场动态测试和室内分级加载动三轴试验,分析了不同压实度的重载铁路路基土体的塑性变形和弹性变形随动应力增大的变化规律,为预测轴重增加条件下的路基稳定性及变形的发展规律提供依据。     

The stability mechanism and its application to heavy-haul couplers with arc surface contact

To investigate the stability mechanism of a type of heavy-haul coupler with arc surface contact, the force states of coupler were analysed at different yaw angles according to the friction circle theory and the structural characteristics of this coupler were summarised. A multi-body dynamics model with four heavy-haul locomotives and three detailed couplers was established to simulate the process of emergency braking. In addition, the coupler yaw instability was tested in order to investigate the effect of relevant parameters on the coupler stability. The results show that this coupler exhibits the self-stabilisation and less lateral force at a small yaw angle. The yaw angle of force line is less than the actual coupler yaw angle which reduces the lateral force and the critical instability. An increase in the friction coefficient of the arc contact surfaces can improve the stability of couplers. The friction coefficient needs to be increased with the increase in the maximum coupler longitudinal compressive force. The stability of couplers is significantly enhanced by increasing the secondary suspension stiffness and reducing the clearance of the lateral stopper of the locomotives. When the maximum coupler compressive force reaches 2500 kN, the required friction coefficient reduces from 0.6 to 0.35, which notably lowers the derailment risk caused by the coupler. The critical instability angle of the coupler mainly depends on the arc contact friction coefficient. When the friction coefficient is 0.3, the critical instability angle was 4–4.5°. The simulation results are consistent with the locomotive line tests. These studies establish meaningful improvements for the stability of couplers and match the heavy-haul locomotive with its suspension parameters.