Classification And Safety Construction Technology Of Surrounding Rock In TBM Construction Of Gaoligongshan Tunnel

TBM is a large-scale integrated tunneling equipment with high degree of mechanization,which can realize efficient and rapid construction.It is widely used in engineering and distributed in many fields such as railway transportation,water conservancy and hydropower,subway,etc.TBM excavation performance analysis,based on the classification of surrounding rock in TBM construction and the safe construction techniques under different surrounding rock conditions are important research topics in this field.The overall analysis of the paper relies on the Gaoligongshan Tunnel of the Dali Railway and introduces the project overview of the Gaoligongshan Tunnel and the“Color Cloud”TBM for engineering design.A large number of data collection and analysis were carried out at the construction site,including basic data analysis such as daily footage,weekly footage,monthly footage,equipment integrity and utilization of tunneling operations;the correlation between excavation performance,geological parameters and tunneling parameters was also studied;The paper also studied the correlation between FPI,geological parameters and excavation parameters;the comprehensive consideration of surrounding rock conditions,support amount,excavation speed and safety risk level based on TBM combined with FPI give the method of surrounding rock classification of TBM construction in Gaoligongshan tunnel.According to the unfavorable geology encountered in the Gaoligongshan tunnel,the safety construction technical schemes such as TBM through fault fracture zone,inrush water and card machine escape are summarized.The research shows that the surrounding rock is dominated by type IV and V surrounding rock,and the amount of support is very large.The TBM footage speed and excavation performance are restricted by surrounding rock conditions and support delays;the TBM equipment integrity rate and failure rate reflect that TBM has good quality and reliability in the Gaoligongshan tunnel;the correlation between TBM excavation performance,geological parameters and excavation parameters is obvious,with the increase of rock compressive strength UCS and integrity K_V,TBM excavation penetration and excavation speed are reduced,the required thrust and Torque increase;multiple regression analysis of FPI,rock uniaxial compressive strength and rock integrity indicates a regular change between them.On-site application of safe construction technology avoids long-term trapping of TBM,ensuring that TBM safely passes through unfavorable geological sections.