Analysis of tunnel water gushing attenuation curve characteristics in red bed: case of Feixianguan Tunnel on Yakang Highway

Water gushing often occurs in karst tunnels during the process of tunnel construction, but there are few precedents in red bed tunnel. Taking Feixianguan Tunnel on Yakang Highway as an example, the prediction curve was fitted based on analyzing the applicability of spring discharge attenuation equation and generalizing the geological conditions. The fitted curve was compared with the measured tunnel inrush flow attenuation curve. The method of “fitting-prediction-comparison” reveals that the measured curve corresponds well with the prediction curve, which proves that the selected equation is suitable and confirms the predicted water gushing source.