Research About The Regularization Of Ground Surface Movement And Deformation Caused By Mountain Tunnel Excavation

The tunnel excavation construction will certainly cause the variation of stress and deformation of the surrounding rock,surronding rock moves towards the inner space of tunnel.when the displacement of surrounding rock is big enough,it will cause ground surface movement and deformation, uneven subsidence of ground surface leads to vertical deformation of ground surface, uneven horizontal displacement is the cause to horizontal deformation of ground surface. If the value of ground surface movement and deformation exceeds a certain limit, it will cause detrimental effect to ground surface buildings above the tunnel,even safety accident. So it is very significant to analyze the regularization of ground surface movement and deformation caused by tunnel excavation construction.The paper uses finite element software MIDAS/GTS simulate the construction process of DuYan tunnel, the regularization of ground surface movement and deformation of mountain tunnels construction and the regularization of surrounding rock movement.Further, this paper also analyzes the influence on tunnel surronding rock displacement and ground surface subsidence by numerical method,caused by five factors of the different surronding rock character , the different excavate method , the different excavated length , the different excavated aperture , the different tunnel depth.At last, analyzing the monitoring data of DuYan tunnel field to provide evidence for judging the stability of tunnel surrounding rock and the time of installing the secondary lining,and take a comparison study with numerical simulation results to prove the reliability of the regularization of ground surface movement and deformation.Research shows that ground surface movement and deformation distribution curve on tunnel cross section are all smooth curves of continuity,the curves of horizontal displacement and the curves of inclination deformation have the similar features,the morphology of horizontal deformation curves of ground surface and the morphology of curvature deformation curves are analogous;the ground surface subsidence occurs in the range of radius of influence, and far away from the axis direction of tunnel ,the value of ground surface subsidence decreases; Along the way of tunnel excavation, the depth of tunnel increases and geological condition changes gradually,the transverse influence range of ground surface movement and deformation enlarges and the strength of influence weakens.The actual ground surface movement of DuYan tunnel by monitoring is consistent to the regularization of ground surface movement and deformation which is concluded by numerical simulation.