高寒山区长大坡道铁路列车下坡限速研究

Study on Speed Limit of Downhill Trains on Long-slope Railways in Alpine and Cold Region

为保证列车运行安全,在长大坡道上必须对列车的下坡速度加以限制,它是计算区间运行时分和制定司机操纵策略的依据,而在高寒山区长大坡道上,列车的速度不仅受坡度影响,与气候条件也有一定关系。文章以30‰长大坡道铁路为例,分别对HXD2双机牵引2 800 t货物列车、HXD1d双机牵引1 200 t旅客列车的下坡限速进行研究。通过分析在雨雪天气轨面潮湿情况下,粘着系数下降对列车制动的影响,按照分段累加法确定出紧急制动距离下的列车限速。根据相关实验数据,分析货物列车下坡调速制动过程中的闸瓦温升情况。最终研究得出:在30‰的坡道上,货物列车下坡限速宜为65 km/h,旅客列车下坡限速宜为110 km/h。研究结论对同类型的高寒山区铁路设计具有一定的借鉴意义。

To ensure the safety of railway operation, the speed of the train in operation on the steep and long slopes should be strictly restricted. This restriction/limitation of speed is the basis for calculation of the travel time and also for development of control strategies for drivers. On long-slope railways in alpine and cold region, the speed of trains is not only affected by slope, but also related to climatic conditions. The article takes long-slope of 30‰ as an example. The other assumptions for this study are as follows:the freight train is driven by HXD2 electric locomotive with maximal load of 2 800 t. The passenger train is driven by HXD1d electric locomotive with maximal load of 1 200 t. The analysis of the speed limitations bases on those two types of trains. Under a certain loading weight, the speed limitation for freight trains is both restricted by the emergency braking distance and the temperature increasing of the braking shoes;the speed limitation for the passenger trains is only restricted by the emergency braking distance. The correlation between the adhesion coefficient and the braking force is analyzed by accumulating the calculation results from separate sections. Based on the relevant experimental data, the problem of the temperature increasing of the wheel and braking shoes is analyzed. Combined with the above aspects, the research eventually got the conclusion:on the railway with long-slope of 30‰, the speed limitation of freight train should be 65 km/h, and for the passenger train should be 110 km/h. The research results have some reference and significance for the railway design in alpine and cold region.