Study on the Deformation Characteristics of a Tunnel Crossing a Large Drop Water-Filled Mine Pit Under Seepage-Stress Coupling
To clarify the stability and deformation characteristics of the entrance slope of a tunnel traversing a large drop water-filled mine pit under seepage conditions,a tunnel project in western China was selected as the engineering background.First,the analytical equations governing tunnel behavior under seepage-only and combined seepage-stress conditions were examined.Subsequently,a series of laboratory tests were conducted to determine the physical and mechanical parameters of the rock and soil surrounding the tunnel.On the basis of these theoretical and experimental results,a three-dimensional numerical model was es-tablished using FLAC3D,and two critical seepage scenarios were designed to assess their effects on the tunnel's surrounding rock and entrance slope.The results show that,when only the stress field is considered,the arch crown exhibits the largest deformation,where-as the inverted arch undergoes the smallest deformation.Under varying pore water pressures,both the vault and arch shoulder experi-ence the greatest deformation,with minimal deformation in the inverted arch.Under the coupled seepage-stress condition,different wa-ter levels in the two accumulated pits induce varying degrees of influence on different parts of the tunnel.Accordingly,it is vital during tunnel excavation to consider methods for blocking or reducing seepage to mitigate adverse impacts on the tunnel structure.
tunnel engineeringfluid structure couplingsurrounding rock deformationslope slipmechanical testingnumeri-cal simulation
万方数据
维普
