KARSTIC WATER DEVELOPMENT REGULARITY AND ITS INFLUENCE ON TUNNEL ENGINEERING OF DIVERSION PROJECT NEARBY KUNMING

Karstic water underground have a great threat to tunnel in karst area, such as cause tunnel water gushing, water inrush, mud in rush, etc. Based on the geological investigation, exploration, pumping test, analyzing karstic water development regularity and its distributed characteristics of diversion project nearby Kunming, and providing the basis of design and construction to water diversion project in Yunnan and future underground tunnel project. Investigation and analysis show that karst developed in Permian, Carboniferous, and Devonian, karst distributed banded near a groundwater discharge datum and fault basin, fault valleys, secondly in the fracture location controlled by new tectonic movement and the boundary of different micro hydrogeological unit; in the Permian limestone, groundwater drainage layered, in the Carboniferous and the Devonian that development aven and underground karst channel; in 1900~2150m elevation, karst development intensively, this area is the main runoff area of karstic underground water and have great influence on tunnel, it have potential of water gushing, water inrush, mud in rush, karst collapse and a karst cavity.