THE GEOLOGIC ROUTE SELECTION IN THE SECTION FROM MEIHUASHAN TO TIANSHENGQIAO ALONG LIUPANSHUI-ZHANYI DOUBLE-TRACK RAILWAY

The section from Meihuashan to Tianshengqiao in Liupanshui-Zhanyi Double-track railway passes through the main cordillera of Meihuashan Mountain. In this area, the landform is obstructive; geological conditions are very intricate; geologic structure, unfavorable geology and special rock and soil are developed, which bring great difficulty for route selection, design and construction of the railway. Comprehensive geological survey methods and means are adopted to find out the regional geological characteristics and the engineering geological conditions of every route scheme, which provide credible basic geological information for route selection. The linchpin geological factors for route selection are the groups of landslides, talus, perilous and falling rocks along Guanyin-River and Shushe-Valley, the disserve of karst-water and karst in long and deep tunnel and the old coal mining area. Through the comparison of the engineering geological conditions, construction quantity and invest of long-tunnel scheme, short-tunnel scheme and outcropping in Guanyin-River scheme of the railway from Meihuashan to Tianshengqiao, the outcropping in Guanyin-River scheme is commended, which is No.1 and No.2 Wumengshan Tunnel passing through the main cordillera of Meihuashan Mountain. The geological conditions are better, construction security is higher, and the aftereffect of construction and operation is very good. This paper offers reference for geologic route selection in the rugged and precipitous mountains of complicated geological conditions.