Experimental Study on the Changing Pattern of Design Parameters of Controlled Drainage in Tunnels
(1. China Railway Engineering Consulting Group Co., Ltd., Beijing 100055; 2. State Key Laboratory of Geological Disaster Prevention and Geological Environment Protection, Chengdu University of Technology, Chengdu 610059)
Abstract：
On the basis of the groundwater seepage theory, this paper uses the analytical calculation method for existing external water pressure reduction coefficients and optimizes the calculation formula for the external water pressure reduction coefficients of tunnel lining under the condition of limited drianage. A large-scale seepage model test system for tunnels was utilized to simulate the limited drainage conditions in the optimized formula through a model test,and a research was conducted into the changing pattern of the reduction factors under comprehensive influence factors, such as tunnel drainage and grouting ring permeability coefficients, as well as into the impact of tunnel drainage and grouting ring permeability coefficients on the design parameters of tunnel drainage control, so as to compare and analyze the formula before and after optimization and to verify its correctness. The results show that: (1) the re? duction factor β decreases with the increase of tunnel drainage design parameter under the same grouting ring permeability coefficient but different drainage volumes; (2) the coefficient m of the tunnel drainage design parameter inreases with the increase of the grouting ring permeability coefficient; and (3) the analysis results after optimization can effectively reflect the actual values and have a wider range of applications than before the optimization.
HUANG Shiguang1 YANG Yanna2 FAN Quanzhong2 HUANG Jingyu2 YU Lei2
.Experimental Study on the Changing Pattern of Design Parameters of Controlled Drainage in Tunnels[J] MODERN TUNNELLING TECHNOLOGY, 2022,V59(3): 201-210
2022, Vol. 59 