Seepage-Stress Coupling Analysis of Water-Rich Loess Tunnel

Abstract

Through engineering example and using the FEM software GTS, water-rich loess tunnel excavation is analyzed without or with the grouting-reinforcement effect and different permeability coefficient of grouting-reinforcement structure. Influence of flow field characteristics and displacement field characteristics caused by variation of grouting-reinforcement structure permeability coefficient in ordinary water level was analyzed. The results show that the permeability coefficient of grouting-reinforcement structure is play an important in the seepage path, pore water pressure and seepage velocity. It also influence in the displacement of surrounding rock. Designs of grouting-reinforcement structure of water-rich loess tunnel should consider impact of seepage-stress coupling effect. First, the waterproofing effect of grouting-reinforcement structure should be considered to, otherwise, it should avoid that the pore water pressure increasing by increase of waterproofing effect of grouting-reinforcement structure, the soil shear strength reducing.

Experimental Investigation of Load-Bearing Mechanism of Underwater Mined-Tunnel Lining

“…Under the combination of water and soil pressures, the stability of the surrounding rock is reduced, and the forces acting on the support structures are increased. In severe cases, catastrophic accidents can occur, such as tunnel collapse, mud burst, and water inrush [44][45][46][47][48][49][50]. Thus, in the present study, to obtain the stress distribution law of the support structure under the influence of external water pressure during the construction and operation of a high-stress water-rich tunnel, a model test system capable of simultaneously considering the water and soil pressures was developed.…”