Research on TBM Jamming Technology in Weak Fracture Zone of Tunnel

A tunnel is affected by the poor geology of the weak fracture zone. During TBM tunneling, problems such as poor self-stability of surrounding rock, easy collapse, and accumulation of slag accumulation occur, resulting in the shield being locked or the cutter head being stuck. To get the TBM out of trouble, the small pilot tunnel construction technology is proposed to carry out new technology of the small pilot tunnel construction from the top of the TBM shield, and the method of long-distance horizontal reinforcement of the bad geology in front of the tunnel face and the cleaning of the slag around the cutter head and shield body is carried out so that the TBM can be smoothly promoted. Under the condition of long and large fault fracture zones, the half-section method construction technology of upper-section excavation and TBM tunneling is proposed to solve the risk of frequent TBM jamming and tunnel collapse. The results show that the construction technology of a small pilot tunnel has the advantages of reducing the risk of jamming, realizing the horizontal advance reinforcement of surrounding rock in front of TBM, shortening the construction period, saving cost and construction.