| The deformation and cracking of operating the tunnel directly affect the safety and operation of the tunnel.So it must be treated.In this paper,the prestressed anchor cable technology is used to reinforce the structure of the heavily deformed tunnel,and the design method and rapid construction technology of the prestressed anchor cable reinforcement are studied,the main research contents are as follows :(1)The applicable conditions of prestressed anchor cable reinforcement of operating the tunnel are studied.The prestressed anchor cable is mainly suitable for the serious deformation cracking of the tunnel caused by the continuous creep of the soft rock,the insufficient thickness of the secondary lining,the insufficient safety of the primary support,the poor bearing pressure of the secondary lining and the deterioration of the surrounding rock.(2)The design and calculation methods of main design parameters of prestressed anchor cable are studied.The main design parameters of prestressed anchor cable include length,spacing,preload and so on.At the same time,the performance of different types of prestressed anchor cable structure is analyzed and improved,and the performance of the improved prestressed anchor cable is tested for laboratory.(3)Using FLAC3D,the numerical simulation analysis of the reinforcement effect of the prestressed anchorage cable of the operating tunnel is carried out.Combined with the actual working conditions of muzhailing railway tunnels,the reinforcement effect of prestressed anchor cable under different working conditions(length of anchor cable,spacing,pre-tightening force)is analyzed,the safety degree of reinforcement of prestressed anchor cable under the condition of the deterioration of surrounding rock and the insufficient thickness of lining is analyzed.(4)The rapid construction technology of pre-stressed anchors cable reinforcement of existing the tunnel is studied.Including drilling,installation and fixing,grouting,stretching and anchor sealing and other major processes.At the same time,the pastries loss law and control measures of the Operational Tunnel reinforced by anchorage cable are analyzed. |
