Abstract：
Considering that improper treatment of water inflow during tunnel construction may seriously affect local ecological and social environments, and using a typical water-inflow section of the Mingtangshan tunnel as an example, this paper proposes a conceptual hydrogeological model for water inflow in a fractured zone based on a small-scale test for hydraulic pressure at a water-stopping point on a typical section. It presents three fissure water-distribution models for the fractured zone before and after excavation. The results show that: 1) a perched water saturated zone in the surface weathered fissure rock layer will appear or disappear after water inflows with the coming of the wet season or dry season; 2) the hydraulic pressure of the water-inflow point increases rapidly after water stopping and then slows down, which can be reflected by a logarithmic model; 3) a water-head depression cone is formed near a single water inflow point, and a balance will be reached by connecting to other interlinked points of water inflow after water stopping; and 4) seven-day monitoring indicates that a stable hydraulic pressure can be achieved after 24 hours of water stopping.
.A Conceptual Water Inflow Model and Characteristics of the Hydraulic Pressure of Water-Stopping Points in the Mingtangshan Tunnel's Fractured Zone[J] MODERN TUNNELLING TECHNOLOGY, 2015,V52(5): 110-116
2015, Vol. 52 