中国至尼泊尔跨境铁路最大坡度研究

中国至尼泊尔跨境铁路穿越喜马拉雅山脉,具有显著的地形高差,海拔从佩枯错4 600 m急骤下降至加德满都1 360 m,部分地段自然纵坡达50‰及以上,需要采用较大坡度以适应地形。在分析国内外大坡度铁路使用及发展的基础上,结合项目地形特点对坡度方案进行分段研究,重点对佩枯错至加德满都段最大坡度方案从运输安全性、运输质量、运输能力和运输经济性等方面综合分析论证。结合长大下坡紧急制动距离的要求,分析客货列车下坡限速,考虑牵引力、制动力、黏着力和车钩强度等限制条件,检算满足长大坡道客货列车牵引、制动安全的牵引质量和编挂辆数,并结合运输需求分析不同坡度方案能力适应性,通过模拟牵引计算比较列车运行速度,计算工程投资、机车购置费和运营费的费用现值,进行经济性比较。综合分析,本项目最大坡度日喀则至佩枯错段暂推荐采用13‰,佩枯错至加德满都段采用30‰。

Study on Maximum Gradient of China-Nepal Cross-border Railway

The China-Nepal cross-border railway crossing the Himalaya Mountains has significant topography altitude difference. The altitude drops sharply from 4 600 m to 1 360 m from Perkhuo to Kathmandu. The natural longitudinal gradient of some sections reaches 50‰ or more, which requires a larger gradient to adapt to the topography. On the basis of analyzing the use and development of large gradient railway at home and abroad, the gradient scheme is studied piecewise in combination with the project topographic characteristics. The maximum gradient scheme of the Pekuco to Kathmandu section is analyzed and demonstrated comprehensively from the aspects of transport safety, transport quality, transport capacity and transport economy. According to the emergency braking distance requirements, this paper analyzes the train downhill speed limits, considering the limiting conditions such as traction and braking force, adhesion and coupling strength, traction quality, and calculates the tractive tonnage and the number of rolling stock to meet the train traction and braking required on long and deep grade. Then it analyzes the adaptability of different gradient schemes based on transport demand, and calculates train speed by simulating traction, and compares the economical efficiency by calculating the cost present value of project investment, locomotive purchase expense and operating cost. The comprehensive analysis recommends 13‰ of maximum gradient for the section from Shigatse to Peikucuo, and 30‰ for Peikucuo to Kathmandu section.