Research On Construction Technology Of Water-mud Bursting Section In Hanlinjie Tunnel

Based on the site survey, hydro-geological data, numerical simulation and other methods, this paper studies mechanism and treatment method of water-mud bursting in Hanlinjie tunnel, which is needed to cross the fault fracture zone and geological contact zone. The primary coverage as follows:(1) Through hydro-geological investigation, the preliminary decision suggests that the disaster of water-mud bursting in the left hole, at ZK88+597, was caused by rock mass weight. Moreover, the key factors are the contact parts of F1fault and the weathered sandstone and the water result from mountain gully at the top of tunnel.(2) The numerical results show that it is necessary to adopt full-section curtain grouting and strengthen the strength of supporting structure for fault fracture zone, and these measures are useful for safe operation of tunnel.(3) Considering the aspects of safety in construction and environmental protection, the treatment measures of water-mud bursting should be considered synthetically. So as to keep stability of surrounding rock, the full-section grouting should be done before the pipe roof and advanced small pipe are carried on. To reduce water pressure on lining, the tunnel waterproof and drainage system should also be reinforced(4) The treatment methods of water-mud bursting need to be applied to the core area of disaster. In order to prevent the chain reaction of geological disaster, deterioration of stability and destruction of existing supporting structure, the adjacent area is also needed to be detected and reinforced.