Distinct element analysis of mechanism of rock fragmentation induced by #br#
TBM cutting in simply composite rock mass with multiple cutters
Jiang Mingjing1,2,3,4 Fu Cheng1 Wang Huaning5 Liu Jun3,4 Liao Youbin6 Chen Youliang6
1. School of Civil Engineering, Tianjin University, Tianjin 300072, China;
2. State Key Laboratory of Hydraulic Engineering Simulation and Safety, Tianjin University, Tianjin 300072, China;
3. State Key Laboratory of Disaster Reduction in Civil Engineering, Tongji University, Shanghai 200092, China;
4. College of Civil Engineering, Tongji University, Shanghai 200092, China;
5. College of Civil Engineering, Tongji University, Shanghai 200092, China;
6. University of Shanghai for Science and Technology, Shanghai 200093, China
Abstract：The PFC2D software, incorporated with a size-dependent bond contact model, was employed to investigate the fracture mechanism induced by TBM cutting in simply composite rock mass. The rock fracture process was simulated under the action of cutting with single, double and triple cutters. The numerical results show that the process of rock fragmentation can be described with three stages: loading stage, unloading stage and residual leap stage. The analysis on the thrust-intrusion depth curve for the cutting in composite rock mass with double and triple cutters demonstrates that the cutter reaches the three stages is slightly slower on soft rock than on hard rock. A large difference was observed between/among cutters on the peak normal thrust, which will induce the wear of the cutters easily. For the rock mass composited by granite and greenschist, contact force chains are segmented by the interface between hard rock and soft rock, and bond breakage of hard rock is more than of soft rock, and through cracks form easily in double and triple cutters breaking rock. Rock breaking efficiency by double cutter is larger than by triple cutter with the latter larger than by single cutter. Besides the breaking efficiency by the double cutter is almost twice as that in other cases.
蒋明镜 傅 程 王华宁 刘 俊 廖优斌 陈有亮. 简单复合岩体中TBM多滚刀破岩机理离散元分析[J]. 土木工程学报, 2019, 52(S1): 120-126.
Jiang Mingjing Fu Cheng Wang Huaning Liu Jun Liao Youbin Chen Youliang. Distinct element analysis of mechanism of rock fragmentation induced by #br#
TBM cutting in simply composite rock mass with multiple cutters. 土木工程学报, 2019, 52(S1): 120-126.
