深长隧道挤压性地层TBM掘进围岩破裂碎胀大变形卡机孕育机理及注浆加固作用机制

This project mainly focuses on the mechanism of ruptured bulking deformation induced shield jamming and its grouting reinforcement mechanism for TBM driving through squeezing rock in long deep tunnels. Based on the 3D printing technology, small size rock samples with detailed microstructures as well as fractured rock mass with complex fracture network are printed. With the printed models, the mechanical and grouting tests are firstly conducted. Based on the test results, the mechanism of the surrounding rock ruptured bulking induced large deformation as well as the grouting reinforcement mechanism for fractured rock mass are then revealed. Due to the powerful capability of Numerical Manifold Method (NMM) in dealing with continuous-discontinuous problems, the proposed mechanical models, which realistically reflect the surrounding rock ruptured bulking process and the fractured rock mass grouting reinforcement process, are developed and incorporated into the NMM platform. Since the structure of the 3D printed models can be controlled, the proposed mechanical models as well as the developed numerical methods are improved and verified by reconstructing the structure of the test models. Finally, based on the developed numerical method, the interaction between the shield and the surrounding rock is investigated. Based on the powerful capability of the developed numerical method, the control mechanism of the ruptured-bulking induced large deformation on the shield jamming disaster is revealed. Compared the contact forces with the thrust forces at the jamming state, the trigger condition and the jamming prediction criterion are proposed. The results concluded from this research would provide theoretical support and analysis tool for the safe and high efficient TBM excavation in long deep tunnels.

本项目围绕深部高应力环境TBM穿越挤压性地层“破裂碎胀大变形卡机孕育机理”及“注浆加固作用机制”两大关键科学问题，借助3D打印技术打印包含细观结构的岩石试样以及包含复杂裂隙网络的碎裂岩体模型进行物理试验，从深层次上揭示深部挤压性地层TBM掘进围岩破裂碎胀大变形机理与碎裂岩体注浆加固挤压扩张→劈裂扩展→渗透扩散→粘结修复作用机制。在此基础上，借助数值流形法强大的连续-非连续分析能力，基于数值流形平台建立反映深部挤压性地层TBM掘进破裂碎胀大变形演化与注浆加固作用过程的数值仿真方法，并通过重建3D打印试样内部结构进行仿真模拟，对比物理试验结果，验证和完善所建立的模型与算法。最后，利用开发的数值仿真平台，模拟TBM掘进围岩与护盾的相互作用，揭示围岩变形时空演化对卡机灾害的作用机理，给出TBM卡机灾害孕育发生的触发条件和卡机状态判别准则，为我国深长隧道TBM高效安全掘进提供理论支持和分析手段。

本项目围绕深部高应力环境TBM穿越挤压性地层“破裂碎胀大变形卡机孕育机理”及“注浆加固作用机制”两大关键科学问题，借助3D打印技术打印包含细观结构的岩石试样以及包含复杂裂隙网络的碎裂岩体模型进行了物理试验，从深层次上揭示了深部挤压性地层TBM掘进围岩破裂碎胀大变形机理与碎裂岩体注浆加固挤压扩张→劈裂扩展→渗透扩散→粘结修复作用机制。在此基础上，借助数值流形法强大的连续-非连续分析能力，基于数值流形平台建立了反映深部挤压性地层TBM掘进破裂碎胀大变形演化与注浆加固作用过程的数值仿真方法，并通过对3D打印试样的数值模型进行模拟计算，并将数值模拟结果对比物理试验结果，验证和完善了所建立的NMM破裂碎胀大变形及注浆加固模拟平台。最后，利用开发的数值仿真平台，模拟了TBM掘进围岩与护盾的相互作用，揭示了围岩变形时空演化对卡机灾害的作用机理，给出了TBM卡机灾害孕育发生的触发条件和卡机状态判别准则，为我国深长隧道TBM高效安全掘进提供了理论支持和分析手段。