Multivariate geological structure of tunnel excavation and support construction technology

According to the excavation to the second tunnel of hydropower station in Xin Jiang. It introduces the watery,loose sand, gravel, shale composite stratigraphic excavation and the support construction technology. During the construction, it follows some principles, including: super anticipation, pipe ahead, grouting, short excavation and less disturbance, strong support, quick closing and strict water measuring. The excavation is optimized and the scheme is supported continuously. Under the premise of ensuring the safety and quality, the construction schedule is accelerated.Thus, the ideal social and economic benefits can be achieved.