Study On Mechanism And Prevention Measures Of High Ground Stress Tunnel TBM Machine

Compared with traditional drilling and blasting method,TBM method has more advantages in construction speed,construction safety and disturbance range of surrounding rock,and is becoming the first choice and important development direction of deep buried long tunnel construction.However,TBM often has to cross deep high ground stress complex strata in long tunnels in western mountainous areas.Under the condition of high stress,the card machine caused by convergent deformation of rock burst and surrounding rock is the main cause of TBM tunnel engineering accident.Therefore,it is necessary to analyze the cause of the accident of the machine in the field,and to prevent the excavation of the tunnel.Based on the investigation of TBM and the analysis of tunnel geology data in the Linzhi Dochon Tunnel project in Tibet,this paper analyzes the mechanism of the tunnel card machine by combining with the computer numerical simulation,and puts forward the corresponding preventive measures.Based on the study of Linzhi Dochon Tunnel project in Tibet and the analysis of TBM construction and tunnel geologic data in the field,the paper analyzes the mechanism of the tunnel card machine by combining with computer numerical simulation,and puts forward the corresponding preventive measures.(1)In this paper,the card machine prediction analysis of the surrounding rock integrity of the tunnel under the condition of high stress is carried out to judge the serious deformation of surrounding rock during the construction of the tunnel and the accident of TBM card machine.In view of the large deformation of surrounding rock caused by the card machine,in this paper,the driving parameters of TBM continuous excavation are analyzed,the regularity of correlation parameters and surrounding rock deformation and frictional resistance is obtained,and the normal shutdown condition of TBM is studied,and the best allowable downtime of TBM under different tunneling parameters is obtained.(2)Rock burst prediction is carried out for the hard Cave section with complete structure of the surrounding rock mass under the condition of high geostress,according to the distinguishing formula of rock burst,the rock burst grade after excavation is given.In view of the particularity of TBM construction and the characteristics of cutter plate,two kinds of unloading blasting schemes are drawn up,and the simulated calculation of unloading blasting by flac3 d The variation of stress and rock burst intensity in tunnel after unloading is obtained.(3)According to the situation of the card machine in the field,according to the different card machine parts of the card machine type classification,and analysis of the reasons for the card machine,refer to the Special section Card machine management measures,summed up the card machine management ideas,and put forward preventive measures.In this paper,the prevention and treatment measures of different types of card accidents under high altitude stress are studied,and the rule of TBM’s driving parameters and frictional resistance under different construction conditions has reference and reference significance for the treatment and prevention of the accident of TBM card machine under the similar condition.