THE EFFECT OF GROUTING REINFORCEMENT ON GROUNDWATER SEE-PAGE IN DEEP TUNNELS

To investigate the effect of grouting reinforcement rim on groundwater pressure and seepage discharge, a number of theoretical analyses have been conducted with the following assumptions: circular tunnel, radial stable and isotropic seepage. The solutions of the seepage flow and the hydraulic pressure distribution law are obtained by the calcula- tions. According to the example, it proved that the grouting reinforcement can obviously de- creased the hydraulic pressure acting on the lining and seepage discharge in drainage condi- tions. The seepage discharge of unlined tunnel calculated by the formulas is close to the ac- tual value obtained from the monitoring data. It illustrates that this method is suitable for the similar tunnels. Additionally, on the basis of the correlation analysis, the water forces acting on the lining and the seepage flow decrease sharply at the beginning by reducing the permea- bility coefficient and increasing the thickness of the reinforcement rim. But when the rein- forcement parameters reach to certain values, the water forces and seepage discharge keep stable regardless of whether the changes of the reinforcement parameters are taken.