A Study on Drainage Stability of Cable Tunnel

전력구 터널의 배수 안정성에 관한 연구

This paper presents the results of 3-D analysis on steady state flow in the region where the leakage in a cable tunnel is occurred due to high excess ground water pressure. In numerical modeling, a relief well is selected as a method of reduction in water pressure at the surrounding region of the cable tunnel. The distribution of ground water level after dewatering by relief wells is analyzed, Results show that the amount of dewatering level in the layer of hard rock is about 4.2∼8.6m, and that in the layer of fracture zone is about 5.8∼8.2m. The predicted settlement at the cable tunnel due to the increase of effective stress by dewatering is 0.3mm.