Failure Characteristics and Mechanical Mechanism of Deeply-Buried Tunnels with High External Water Pressure for Drill &Blast and TBM Methods
(1 State Key Laboratory of Geohazard Prevention and Geoenvironment Protection, Chengdu University of Technology,Chengdu 610059;2 Huadong Engineering Corporation Limited, PowerChina ,Hangzhou 310014)
Abstract：
Drill&blast and TBMs are two main methods for excavating underground works, and both have a signifi? cant impacts on the disturbance degree and reinforcement measures of surrounding rock. Based on four large parallel tunnels adopting the TBM and drill&blast methods, the influence of the excavation method on surrounding rock damage is studied. Through statistical processing of geological data and mechanical analysis, the failure modes of the tunnel′s surrounding rock are summarizedand common features of the effects of the two construction methods on the surrounding rock are concluded. In addition, a comparison of the effects of the two construction methods on the surrounding rock are conducted, and it is determined that the secondary failure range by TBM is larger than that of the drill & blast method and a TBM is inclined to produce rock bursts and stress failure, while structural plane failure is more likely to occur when the drill& blast method is adopted. Furthermore, mechanical mechanisms of various failures are analyzed based on the above
.Failure Characteristics and Mechanical Mechanism of Deeply-Buried Tunnels with High External Water Pressure for Drill &Blast and TBM Methods[J] MODERN TUNNELLING TECHNOLOGY, 2017,V54(5): 138-145
2017, Vol. 54 