实例分析隧道建设对岩溶水的影响

贵州省是岩溶地貌发育的地区，在进行铁路建设时经常遇到隧道工程与地下岩溶水系统相互干扰的问题，文章以磨雄隧道和银山隧道为例，借助大地电磁解译和MIDAS-GTS程序计算，阐述岩溶地下水系统与隧道建设的不和谐关系。磨雄隧道施工后，居民饮泉点干涸，水位未按预期设计恢复，造成原本饮水紧缺的山区雪上加霜；银山隧道施工中遭遇罕遇暴雨，竖直侧墙被突增岩溶水压爆，侧墙破坏长度达20 m，中断列车通行超过24 h。因此建议贵州地区隧道建设的前期选线时，要查清岩溶地下水系统边界，尽量避让岩溶强烈发育地段，设计期应充分考虑岩溶水可能造成的危害，施工期对所遇岩溶水通道宜通不宜堵。 

Influence of tunnel construction on karst water: Case analyses

Karst areas and karst water are widely present in Guizhou Province.The interaction between tunnel construction and karst water has long beena problem encountered in railway projects in Guizhou. Using the Moxiong and Yinshan tunnelsas examples, this paper attempts to address this issue. Via the interpretation of magnetotelluric data and the application of MIDAS GTS, groundwater problem and its disharmonious relationship with the tunnel are analyzed.After the construction of the Moxiong tunnel was commenced, the groundwater level droppedand did not recoveras expected in the springs at nearby residences, leading to the withering of the springs and severe water shortage in the communities. Yinshan tunnel on the other hand had experienced asevere rainstorm, as a result the karst water pressure elevated and eventually blasted one of the vertical side walls, which damaged the tunnel in a length up to 20 meters, interrupting train pass for more than 24 hours. The lessons from these examples suggest that when selecting the tunnel line in Guizhou, the boundaries of karst water systems should be clarified to avoid the areas with well-developed karst water. In the design stage, full consideration should also be taken to avoid any possible hazard from karst water. During the construction of tunnels, the karst channels encountered should be dredged rather than plugged.