高地应力-复合岩体耦合作用下TBM刀具破岩机理研究

In the deep complicated formation, because of the features of high geostress, diversification of lithologic character and rock mass structure, Tunnel Boring Machine (TBM) always suffer from not operation, abnormal cutter wear, incontrollable direction of the cutterhead and low boring speed. In order to smoothly and safety operation of TBM tunneling in deep complicated formation, it is significant to research the mechanism of rock fragmentation by TBM cutters under the coupling of high geostress and composite rock mass. In this study, the methods of linear cutting test and general particle dynamics (GPD) numerical simulation will be used to study the characteristics of rock fragmentation, cutting force and rock-breaking efficiency. The process of rock fragmentation by TBM disc cutters and drag bit will be researched, and the laws of cracks initiation and propagation in the innerior of composite rock mass and the interface of soft and hard rock will be analyzed. The relationship of rock fragmentation characteristics and cutting force will be researched in deep complicated formation. The effects of the coupling of high geostress and composite rock mass on the rock boreability index and TBM excavation efficiency will be obtained. The results of this study can improve the TBM excavation state evaluation, leading to the effective and safe TBM excavation in deep complicated formation.

深部复合地层具有地应力高、岩性及岩体结构多变等特征，全断面掘进机(TBM)在深部复合地层中掘进时极易出现卡机、刀具异常磨损、刀盘方向难以掌控、掘进速率降低等问题。为了确保TBM在深部复合地层中安全顺利掘进，研究高地应力与复合岩体耦合作用下TBM刀具破岩机理具有重要意义。本项目拟采用TBM刀具线性切割试验与广义粒子动力学(GPD)数值模拟试验，分析高地应力与复合岩体耦合作用对TBM滚刀和切刀联合破碎岩体特征、破岩力及破岩效率的影响。研究高地应力与复合岩体耦合作用下TBM滚刀和切刀联合破岩的物理过程，分析复合岩体内部及软硬岩界面裂纹起裂及扩展规律，揭示深部复合地层TBM刀具破岩机理；研究深部复合地层中TBM刀具作用下的破岩特征与破岩力的关系，得到高地应力与复合岩体的耦合作用对高地应力复合岩体的可掘性指数以及破岩效率的影响，为TBM在深部复杂地层中掘进性能的预测提供理论依据。

深部复合地层具有地应力高、岩性及岩体结构多变等特征，全断面掘进机(TBM)在深部复合地层中掘进时极易出现卡机、刀具异常磨损、刀盘方向难以掌控、掘进速率降低等问题。为了确保TBM在深部复合地层中安全顺利掘进，研究高地应力与复合岩体耦合作用下TBM刀具破岩机理具有重要意义。本项目采用TBM刀具线性切割试验与广义粒子动力学(GPD)数值模拟试验，得到了不同地应力下 TBM 滚刀和切刀联合作用于软硬复合岩体时，复合岩体内部宏观裂纹起裂及扩展和微观损伤破坏机制，尤其是软硬岩界面的裂纹扩展及破裂规律，揭示了不同地应力下 TBM 滚刀和切刀联合破岩时软硬复合岩体的宏/微观破坏机理。通过研究深部复合地层中 TBM 滚刀和切刀联合作用的破岩特征与破岩力的关系，得到了符合邦德假说和黎金格新表面说的最优法向力和特征粒径的关系，这对推进复合地层中TBM滚刀破岩理论及TBM掘进法向力的选取具有重要的理论与实践意义。