Mechanical Characteristics of Main Structure of Mining Tunnel under Water Pressure

In order to probe into the mechanical characteristics of main structure of a mining tunnel under the action of water pressure, model tests were carried out for investigating the mechanical characteristics of tunnel, the interaction between lining and strata and the failure modes of the structure were researched. Non-uniform water pressure-soil pressure device for a horseshoe-shaped tunnel section was designed. The mechanical characteristics of main structure subjected to water pressure and soil pressure were simulated experimentally. The reserach result demonstrates that moment has a butterfly-shaped distribution along lining perimeter, and the distribution of axial force appears as an ellipse. With the raise of soil pressure, bending moment, axial force, deformation, and eccentricity of lining increase. The increase of lateral pressure coefficient will lead to the reductions of bending moment and axial force. In addition, water pressure will influence the axial force of lining sharply and bending moment gradually. Consequently, limited water pressure is less than 500 kPa.