Current practice for estimating water inflow rate relies mostly on analytical solutions which assume a homogeneous, isotropic porous medium around a tunnel. Field measurements indicate that current engineering practice does not consistently make adequate estimate of ground-water flow into a tunnel during excavation due to various factors that analytical solutions do not properly take into account. Among the various factors affecting ground-water flow, the significance of a highly pervious feature located near the tunnel is discussed in this research. The highly pervious feature, which is located near an underground opening and connected to a large source of water, can provide a path for relatively high-head water to the joints intersecting the opening. This paper describes the influence of a highly pervious feature on the ground-water flow regime around a tunnel and the change of inflow rate as the tunnel approaches a highly pervious feature.
All Science Journal Classification (ASJC) codes
- Geotechnical Engineering and Engineering Geology