TBM掘进煤矿深部巷道围岩准静态卸荷力学响应

Introducing TBM in excavation of deep-buried roadways plays a significant role in enhancing advance rate and safety of excavation operations. Nevertheless, considering special geological setting of deep strata within coal mines, the mechanical response mechanism of TBM-excavated roadway surrounding rocks is still unclear. This project plan to be conducted through theoretical analysis, numerical simulation and laboratory tests. Firstly, the triaxial unloading tests that are capable of represent the quasi-static unloading mechanical characters of TBM excavation need to be carried out. The damage and deformation characters of rocks under various confining pressure and unloading speed will be analyzed, and the thresholds of different stages of rock damage and deformation will be defined. Moreover, the damage and deformation mechanics of rocks under quasi-static unloading will be revealed. Secondly, the strength criterion and dynamic evolution equation of strength parameters of rocks will be obtained on the basis of triaxial unloading test results. Therefore, the damage constitutive model of rocks under quasi-static unloading will be established. Finally, base on proposed constitutive model, the theoretical model and continuous-discontinuous coupling numerical model will be established and be applied within calculations. The quasi-static unloading mechanical response mechanism of surrounding rocks of TBM-excavated coal mine roadway will be revealed in the end. This project will be capable of providing scientific basis for optimizing support design of TBM-excavated coal mine deep-buried roadway.

采用TBM掘进煤矿深部巷道对于提高岩巷掘进效率和安全性意义重大。但煤矿深部地层地质条件特殊，TBM掘进煤矿深部巷道围岩力学响应机理尚不明晰。本项目拟采用理论分析、数值模拟和室内试验的方法，首先开展反映TBM掘进扰动特性的岩石三轴准静态卸荷试验，分析不同围压和卸荷速率下的准静态卸荷岩石损伤变形规律，明确岩石损伤变形各阶段的临界特征，揭示准静态卸荷条件下岩石变形特性与损伤演化机理。其次，基于三轴卸荷试验，获得岩石卸荷强度准则和强度参数动态演化方程，建立准静态卸荷条件下岩石损伤本构模型。最后，根据构建的本构模型，建立TBM掘进煤矿巷道围岩力学响应的理论模型和连续-非连续耦合数值模型，并进行计算分析，最终揭示TBM掘进煤矿深部硬岩巷道围岩准静态卸荷力学响应机理。为优化TBM掘进煤矿深部巷道围岩支护设计提供科学依据。

采用TBM掘进煤矿深部巷道对于提高岩巷掘进效率和安全性意义重大。但煤矿深部地层地 质条件特殊，TBM掘进煤矿深部巷道围岩力学响应机理尚不明晰。本项目采用理论分析、数值模拟和室内试验的方法，首先开展反映TBM掘进扰动特性的岩石三轴准静态卸荷试验，分析了不同围压和卸荷速率下的准静态卸荷岩石损伤变形规律，明确岩石损伤变形各阶段的临界特征，揭示准静态卸荷条件下岩石变形特性与损伤演化机理。同时开展了TBM掘进巷道围岩蠕变试验，基于三轴卸荷试验和岩石蠕变试验，获得了TBM掘进扰动下岩石卸荷强度准则和强度参数动态演化方程，建立准静态卸荷条件下岩石损伤本构模型和岩石蠕变本构方程。最后，根据构建的本构模型，建立了TBM掘进煤矿巷道围岩力学响应的理论模型和离散单元法数值模型。开展了TBM掘进扰动条件下煤矿深井巷道围岩扰动规律理论分析、数值模拟计算分析，并通过施工现场监测数据验证了计算结果的准确性。最终揭示TBM掘进煤矿深部硬岩巷道围岩准静态卸荷力学响应机理，为优化TBM掘进煤矿深部巷道围岩支护设计提供了科学依据。