Model test study on the distribution law of underwater tunnel seepage field

Water pressure is a key indicator of the underwater tunnel design. Using the indoor model test system, the distribution law of the seepage field of the underwater tunnel is investigated. The distribution law of the water pressure at the outer surface of the grouted ring and the lining back associated with different drainage systems is obtained: The water pressure of lining back decreases rapidly with the increase of the displacement,; when displacement reaches a certain level, the rate of size reduction decreases gradually until the pressure value is close to zero; In the horizontal and vertical directions, from the surface of the soil above the tunnel to the vault, water pressure demonstrates distribution of hydrostatic pressure; In the grouting circle,, water pressure decreases rapidly, which shows that reduction effect on the water pressure of grouting circle is significant. Through the study of changing the thickness and the permeability coefficient of the grouting circle, it is shown that at the same displacement, the pressure of lining back and edge of grouting circle decreases with the increase of the thickness of grouting circle; the pressure of lining back and edge of grouting circle increases with the decrease of the permeability coefficient of grouting circle. ©, 2015, Editorial Office of China Civil Engineering Journal. All right reserved.