Abstract:To explore the influence of shallow buried three-hole tunnel construction on strata, this paper solved the elastic solution of three-hole circular tunnel excavation in a semi-infinite plane by employing the complex function theory and the Schwarz alternative method. Meanwhile, the finite element model for tunnels was built to obtain the numerical results, which were compared with the complex function solution. In addition, relevant parameter analysis was conducted on two layouts of the parallel three-hole tunnel layout and wedge-shaped tunnel layout to obtain the stratum deformation distribution law under different shallow three-hole tunnel spacing and burial depths. The results show that the complex function solution based on the stress boundary conditions is in sound agreement with the numerical solution, and the distribution law of surface sedimentation deformation is basically consistent. Under the parallel layout, the construction disturbance between three-hole tunnels weakens with the increasing ratio of spacing to the diameter. When this ratio is 2, the relatively independent peak value of stratum sedimentation is formed above the respective caverns of three-hole tunnels. Under the wedge-shaped layout, with the rising burial depth of the three-hole tunnels, the vertical displacement of the three-hole tunnels decreases, while the influencing range of the contour line of vertical displacement of the strata expands.