深部高渗透水压作用下岩石流变力学特性试验与模型研究

The increase of exploitation depth in coal mine also result in a continuous increase of seepage water-pressure, which also leads to more obvious deformation failure of deep tunnel in coal mine. Deep tunnel under the action of high seepage water-pressure usually appears an obvious characteristic with rheological large deformation. Therefore, it is very significant to investigate rheological mechanical behavior of rock under the action of deep high seepage water-pressure, which has important practical value for ensuring the long-term stability of deep underground rock engineering. This project focuses on the long-term stability of surrounding tunnel in deep coal mine engineering. By using rock servo-controlled triaxial rheological system and rock acoustic emission measurement equipment, triaxial rheological experiment is carried out for deep rock material under the action of high seepage water-pressure. On basis of experimental results, triaxial rheological deformation behavior of rock material under the action of high seepage water-pressure is investigated and the evolution law of permeability coefficient is analysed. The effect of different water-pressure and seepage-stress coupled action on the rheological deformation and long-term strength of rock is explored. At the same time, this project will clarify the rheological damage behavior of rock under high water-pressure and complex loading path, and obtain evolution characteristics of long-term strength attenuation and time-effect failure mechanism of rock under the action of different seepage water-pressures. On theoretical aspect, triaxial rheological constitutive model of rock by taking into account the action of seepage water-pressure will be put forward and theoretical equation between seepage water-pressure and modelling parameters of rock rheology also will be constructed. The results will can be used to predict the long-term stability and to provide technical support and guidance basis for deep underground tunnel engineering under the action of high seepage water-pressure.

煤矿开采深度的逐渐增加，使得渗透水压在不断地升高，由此导致深部巷道围岩变形破坏更为严重，呈现出显著的流变大变形特点，因此研究深部高渗透水压作用下岩石流变力学特性，对于确保深部矿山地下工程长期稳定具有重要实践意义。本项目拟以深部矿山巷道围岩长期稳定与安全为研究目标，采用岩石全自动三轴流变伺服系统与岩石声发射测试仪等先进设备，开展高渗透水压作用下岩石三轴流变力学试验，研究高渗透水压作用下岩石流变变形特性，分析岩石长期流变过程中渗透系数的演化规律，探索不同水压力以及渗流-应力耦合作用对岩石流变变形与长期强度的影响，明确高水压以及复杂加载路径下岩石流变损伤特征，获取不同渗透水压作用下岩石长期强度衰减演化特征和时效破坏机理，提出考虑渗透水压作用的岩石三轴流变本构模型，建立渗透水压与岩石流变本构模型参数之间的理论关系式。研究结果可为深部矿山高渗透水压作用下巷道围岩长期稳定提供技术支持和指导依据。

地下工程开采深度的逐渐增加，使得渗透水压在不断地升高，由此导致深部地下工程围岩变形破坏更为严重，呈现出显著的流变大变形特点，因此研究深部高渗透水压作用下岩石流变力学特性，对于确保深部地下工程长期稳定具有重要实践意义。本项目拟以深部地下工程围岩长期稳定与安全为研究目标，采用岩石全自动三轴流变伺服系统与岩石变形损伤量测等先进设备，基于复杂状态下岩石瞬时力学特性试验结果，开展了高水压作用下岩石三轴流变力学试验，探讨了岩石流变参数(包括流变应变，稳定流变速率和黏滞系数)与轴向偏应力、水压的关系，讨论了水压与偏应力水平对饱和红砂岩流变变形的影响机理；研究了渗流应力耦合作用下岩石流变变形特性，分析了岩石长期流变过程中渗透特性的演化规律，探索了渗流-应力耦合作用对岩石流变变形与长期强度的影响，明确了复杂加载路径下岩石流变损伤特征，获取了不同渗透水压作用下岩石时效破坏机理；基于流变试验结果，建立了多个岩石非线性流变损伤本构模型，不仅可以合理描述岩石加速流变特征，而且可以反映岩石卸载流变特征。研究结果可为深部高渗透水压作用下地下工程围岩长期稳定提供技术支持和指导依据。