成贵铁路岩溶特征及线路选线

Research on the Karst Characteristics and Route Selection of Chengdu-Guiyang Railway

研究目的:成贵铁路途经云贵川三省,可溶岩占研究区总面积的55%,段落总长197 km,沿线地表岩溶塌陷、溶洞、暗河等岩溶形态发育,规模普遍较大。为保障铁路施工及运营安全,以及为线路方案及工程设置选择提供依据,勘察需查明线路各方案的岩溶发育情况。研究结论:(1)研究区可分为3个区(四川盆地边缘褶皱带区、四川盆地-云贵高原过渡带区、云贵高原区)、4种不同的岩溶体系(栖霞茅口组岩溶体系、水平缓倾层间岩溶体系、倾斜岩层岩溶体系、倾伏褶曲封闭式岩溶体系);(2)通过不同水文地质单元、体系内岩溶发育环境的差异研究,找出岩溶发育的薄弱区及发育高程,使线路平面及竖向上得以最大程度绕避岩溶;(3)通过岩溶发育情况及岩溶水的量化研究,为线路方案选择、工程治理可行性提供了依据;(4)本研究成果可为岩溶区铁路、公路、地下工程、深基坑(井)勘察设计提供参考。

Research purposes:The Chengdu-Guizhou Railway passes through the three provinces of Yunnan,Guizhou and Sichuan.Soluble rock occupies 55%of the total area of the study area,and the total length of the section is197 km.Karst morphology of surface karst collapse,karst caves,and dark rivers along the line develops,and the scale is generally large.In order to ensure the safety of railway construction and operation,as well as to provide a basis for the selection of route schemes and engineering settings,the investigation must find out the karst development of each route scheme.Research conclusions:(1)The study area can be divided into 3 areas(Sichuan Basin marginal fold zone,Sichuan Basin-Yunnan-Guizhou Plateau transition zone,Yunnan-Guizhou Plateau region)and 4 different karst systems(Qixia Maokou formation karst system,horizontal slow-declination interlayer karst system,inclined rock karst system,and declin-fold closed karst system).(2)Through the study of the difference of karst development environment in different hydrogeological units and systems,the weak area and development elevation of karst development are find out,so that the line can avoid karst to the greatest extent in the plane and vertical direction.(3)The karst development and karst water quantitative research provide a basis for the route plan selection and engineering management feasibility.(4)The research results can provide reference for survey and design of karst railways,highway,underground engineering,and deep foundation pit(well).