关键词: 深埋特长隧道;涌水量预测;涌水动态影响半径;断裂构造;

Abstract: Under combined influences of fracture tectonics and precipitation, a certain scale water-rich faults have been formed in the igneous region.When tunnels pass through such regions, it is highly possible to cause water gushing and loss of life and equipment.For the above water gushing problems, according to the analysis of the water-rich fault fracture section characteristics in the igneous area, the tunnel water gushing was considered to be composed of two major components: those released from bedrock fractures and those from precipitation infiltration.The former was predicted by the groundwater desiccation method, while the latter was predicted by the precipitation infiltration method.On this basis, in order to gain a higher accuracy of the prediction results, the influence radius fitted by the measured data was involved in the calculation, and a method for water gushing prediction was deduced based on the influence radius.Finally, an example of Hongtu Tunnel was illustrated for verification.The results showed that:(1) within a rainfall cycle, the larger average thickness of the aquifer(Hn)there was, the higher growth rate of the corresponding influence radius(Rn)would be.(2) With the increase of the time T,the growth rate of the radius of influence Rn was gradually reduced.(3) The error of the calculation results of the proposed method and the actual monitoring data was within 10%,and the accuracy was high.The research results can provide theoretical guidance for the construction of underground projects under similar geological conditions.

Key words: deep-buried long tunnel; prediction of water gushing; dynamic influence radius of water gushing; fracture structure;