Major engineering geological problems of the Qinling-Dabashan segment of the Three Gorges Water Diversion Project, China. Geological Bulletin of China

Based on regional engineering geological conditions analysis and linear investigations, the major engineering geological problems of the Qingling-Dabashan sector of the Three Gorges Water Diversion project are analyzed and assessed using engineering geological analogy method in which stress on major engineering geological problems related to active faults and deep buried tunnels construction in the Qingling-Dabashan Mountainous region. This paper primarily reveals that the major orientation of the 14 regional faults is close to east-west direction, which vertically cross the diversion tunnels and with significantly activity differences with the present situation, among which the Dabashan arc fault, the Lingshan-Lizhaping fault, the Shiquan-Ankang fault and the Sanhuashi-Hanwangcheng fault are the relative stronger activities and larger scale fault, and also located at the key part of the Diversion Project, which might result in water inrush and large deformation in tunnels. Furthermore, This paper ascertains that there are serious potential rock burst and water inrush hazards related to the deep buried tunnels in the Qingling-Dabashan Mountain region, especially the potential strongest Rock burst near the Qingling main peak and the large scale water inrush related to faults and Karst near the Dabashan, and great attention should be paid to the above mentioned potential problems.