Abstract:
Water inflow and mud burst occurred frequently in the Yonglian tunnel passing through fault fracture zone, seriously affecting tunnel construction and operation safety. Geophysical prospecting and advanced drilling method were used to determine the spatial location, distribution pattern and water abundance of confined aquifer in unfavorable geology body. Based on the exploration results, relevant treatment measures for left and right tubes were conducted, such as in-situ hole cleaning and grouting of the key drill holes with water inflow in left tube, dense hole drilling and grouting of left tube in aquifer zone, thickening of grout curtain reinforcement circle of key sections, water drain and energy release by hole drilling and then grouting in working chamber of right tube. Evaluation of grouting effect and actual excavation result show that the treatment effect of confined aquifer is fine, the strength, stability and permeability of rock mass in aquifer area are significantly improved and the tunnel successfully passes through F2 fault fracture zone with the above mentioned method.
WANG Deming WU Yueyue SUN Huadong TIAN Shanjun
.Exploration of Large Confined Aquifer of the Yonglian Tunnel and Relevant Treatment Measures[J] MODERN TUNNELLING TECHNOLOGY, 2019,V56(3): 147-153