关键词: 岩溶隧道;涌突水;涌水量;降雨;地下水;时空特征;中梁山隧道群;隔拦式结构;

Abstract: The mountain city Chongqing is densely distributed with tunnels.The problem of groundwater inrush in tunnels is more prominent under the geological conditions of stall-type tectonics, of which the section between the Changjiang River and the Jialing River in Zhongliang Mountain is particularly typical.The observed discharge quantity of groundwater inrush were sorted out for 17 tunnels from 1970 to 2020,as well as the rainfall data.Based on the understanding of regional hydrogeological conditions, the spatio-temporal characteristics of groundwater inrush were summarized by means of the statistical analysis and geological condition analysis.The results showed that the amount of tunnel inrush had a good correlation with the rainfall, the groundwater system was mainly recharged by rainfall, and the inrush in early time showed a quicker response to the rainfall.The finding reflected the overall decline of the regional groundwater level after the large-scale tunnel construction.The spatial differences of the groundwater inrush demonstrated some characteristics.Firstly, the groundwater inrush mainly occurred in the soluble rock stratum.Secondly, the inrush of west wing was larger than the east due to the more steeply inclined stratum.Finally, the longitudinal fold shape along the axis of the Guanyinxia anticline substantially controlled the direction of regional groundwater flow.The results can provide a reference for tunnel construction and groundwater inrush disaster prevention in the similar geological conditions of this area.

Key words: karst tunnel; groundwater inrush; rainfall; groundwater; spatio-temporal characteristics; Zhongliang Mountain; tunnel group; stall-type tectonics;