渗流及软化效应对隧洞围岩应力分析

Stress Analysis of Surrounding Rock of Tunnel under Seepage and Softening Effect

以水工隧道为研究对象,分析各因素对水工隧道应力分布的影响。当不均匀渗透系数小于1时,越靠近0°,孔隙水压力曲线增速较快;当不均匀渗透系数大于1时,越靠近90°,孔隙水压力曲线增速越快;当不均匀渗透系数小于1时,角度为0°的孔隙水压力小于90°。当角度为0°或90°时,孔隙水压力受不均匀系数影响较小。当中间主应力系数为1时,有围岩最大径向应力;当中间主应力系数为0时,有围岩最小径向应力。当塑性区半径不变时,中间主应力系数对围岩应力状态有一定的影响;中间主应力系数对围岩压力的影响程度小于支护反力对围岩压力的影响程度。

This research takes hydraulic tunnel as the research object, analyzes each factor to the hydraulic tunnel stress distribution influence. When the non-uniform permeability coefficient is less than 1, the closer to 0°, the faster the pore water pressure curve increases. When the non-uniform permeability coefficient is greater than 1, the closer to 90°, the faster the pore water pressure curve increases. When the inhomogeneous permeability coefficient is less than 1, the pore water pressure with an angle of 0°is less than 90°. When the angle is 0° or 90°, the pore water pressure is less affected by the non-uniformity coefficient. When the intermediate principal stress coefficient is 1, there is the maximum radial stress, and when the intermediate principal stress coefficient is 0, there is the minimum radial stress. When the radius of plastic zone is constant, the intermediate principal stress coefficient has certain influence on the stress state of surrounding rock. The influence of intermediate principal stress coefficient on surrounding rock pressure is less than that of support reaction.