Research on the treatment technology for large heaving deformation in working face for vertical shaft at Xianglushan tunnel

XU Huibin; CHEN Zhenguo; ZHANG Chu; CHEN Jun; YANG Xue

doi:10.19458/j.cnki.cn11-2456/td.2025.04.006

Abstract：In order to control the large deformation of the vertical shaft working face in Xianglu Moun-tain Tunnel and solve the problem of soft rock support caused by erosion,numerical simulation tech-nology was used to analyze the mechanism of large deformation of the working face during lifting.Due to the fragmentation of the surrounding rock structure,the horizontal structural stress in the site area is high,the shear dilation effect of the fractured surrounding rock in the working face is obvious after excavation.Under the continuous compression of horizontal stress,the surrounding rock of the vertical shaft working face undergoes significant uplift deformation towards the free side.A compre-hensive treatment plan of advanced"consolidation grouting+strengthening support+stress release"is adopted to address the deformation characteristics of the surrounding rock in the vertical shaft working face.Firstly,the full section consolidation grouting of the working face is carried out,with straight hole grouting used in the middle of the working face and inclined hole grouting used at the ed-ges.Cement based grout is used to modify and reinforce the fractured surrounding rock;Then,strengthen the support for the wellbore and the soft rock in the erosion zone,set up two rings of pres-tressed anchor cables on the wellbore,and use pipe shed advanced support for the soft rock in the ero-sion zone;Finally,before resuming excavation,a pressure relief groove is used to release stress from the surrounding rock of the working face and alleviate the stress environment of the working face.Af-ter the governance was completed,the excavation face smoothly passed through the rock erosion sec-tion,and the large deformation of the face was well controlled.