Abstract With respect to mined metro tunnelling in mixed ground, a combined phreatic water and fissure water media analysis model is established based on the continuous porous media model for a phreatic aquifier, a formula and specific parementer values used to predict fissure water inflow are derived in light of the dynamics of groundwater, and the application method for the above formula for predicting water inflow at the grouting-reinforced section of metro tunnels is put forward. Using the Qingdao metro tunnel as an example, the water inflow is predicted by the analytical method and the numerical analysis method, respectively, and is compared with the measured values at the site. Analysis results show that the estimation error is lower for the analytical method. In addition, the effects of different tunnel shapes on water inflow are analyzed and it is concluded that the section type has little effect on the water inflow. Thus, the derived analytic formula has high applicability for predicting water inflow in mined metro tunnels in combined rock and soil strata.
Abstract：
With respect to mined metro tunnelling in mixed ground, a combined phreatic water and fissure water media analysis model is established based on the continuous porous media model for a phreatic aquifier, a formula and specific parementer values used to predict fissure water inflow are derived in light of the dynamics of groundwater, and the application method for the above formula for predicting water inflow at the grouting-reinforced section of metro tunnels is put forward. Using the Qingdao metro tunnel as an example, the water inflow is predicted by the analytical method and the numerical analysis method, respectively, and is compared with the measured values at the site. Analysis results show that the estimation error is lower for the analytical method. In addition, the effects of different tunnel shapes on water inflow are analyzed and it is concluded that the section type has little effect on the water inflow. Thus, the derived analytic formula has high applicability for predicting water inflow in mined metro tunnels in combined rock and soil strata.
2015, Vol. 52 