Abstract：
Semi-enclosed waterproofing is adopted for mountain tunnels in most cases; this effectively decreases water pressure against the lining, but also results in a loss of groundwater resources. Based on a tunnel transient seepage model and under the condition of semi-enclosed waterproofing, the water drainage volume and water level variation during tunnel construction and operation are researched and the distribution law of water pressure against a lining in operation is established. Furthermore, the influence of the range and parameters of curtain/radial grouting on the water drainage volume, water level and water pressure are examined, showing that ground consolidation grouting can reduce both the water pressure against the lining and the loss of groundwater resources, achieving a win-win effect on the interaction between the tunnel and the groundwater. Finally, whether a drainage system for an invert is set or not is also discussed.
2015, Vol. 52 