基于运输质量和运输能力的高速铁路长大坡道设置研究

针对我国西部地区高速铁路建设出现的长大坡道,从上坡对运输质量影响和下坡对运输能力影响两方面研究高速铁路的长大坡道设置问题。通过列车模拟牵引计算,研究250 km/h动车和350 km/h动车在15‰~30‰上坡道的运输质量下降情况,提出在困难艰险山区,长大坡道坡长设置可考虑动车组在大坡道上的运行速度不低于设计速度的70%。从最制约运输能力的列车到达间隔出发,分析长大坡道设置对列车到达间隔的影响,采用CRH380BK+CTCS3-300T车型车载,以250,300 km/h为制动初速,分别测算-15‰,-20‰,-25‰,-30‰理论连续坡道下的列车到达间隔。计算结果表明,若要满足5min的追踪间隔时间,或采取限速措施,或对大坡道的长度加以限制,基于CRH380BK+CTCS3-300T监控制动距离数据,给出列车运行限速和大坡道坡长设置的建议。研究表明,对于设计速度300 km/h及以上的高铁线路,大坡道长度设置建议维持原设计规范标准;对于设计速度250 km/h的高铁线路,30‰坡道长度建议不宜大于4 km,25‰坡道建议不宜大于5 km,20‰坡度建议不宜大于8 km。

Research on Setting of Continuous Long and Steep Grade in High-speed Railway Based on Transport Quality and Transport Capacity

Aiming at the long and steep grades in the construction of high-speed railway in western China, this paper studies the problem of setting the long and steep grade of high speed railway from two aspects: the effect of long and steep uphill grade on transport quality, and the effect of long and steep downhill grade on transport capacity. By simulated train traction calculation, the speed reduction ranges of the 250 km/h and 350 km/h multiple units running on slope of 15‰ to 30‰ are studied. According to simulation results, it is proposed that the running speed of multiple units on uphill grade in difficult and precipitous mountainous area should not be lower than 70% of the designed line speed. From the perspective of the train arrival interval that most restricts the transport capacity, the influence of setting long and steep grade on train arrival interval is analyzed. Adopting CRH380BK MU carrying CTCS3-300T train control onboard equipment, the train arrival interval on the theoretical continuous grade of-15‰,-20‰,-25‰ and-30‰ is calculated respectively with 250 km/h and 300 km/h as the initial braking speeds. The calculation results show that in order to meet the tracking interval of 5 min, either speed limit or steep grade length restriction should be performed. Based on the monitoring braking distance data of CRH380BK MU carrying CTCS3-300T train control onboard equipment, this paper gives suggestions on the limit of train operation speed and the setting of steep grade length. Research results show that: for high-speed railway lines with the design speed of 300 km/h and above, it is recommended to follow the specifications of The Code for Design of High Speed Railway for setting steep grade length; for high-speed railway lines with the design speed of 250 km/h, the length of 30‰ slope is recommended to be less than 4 km, the length of 25‰ slope less than 5 km, and the length of 20‰ slope less than 8 km.