黏弹性波传播与其诱致岩石损伤演化的相互作用机理

Rocks are viscoelastic under dynamic loading. Viscoelastic wave propagation and dynamic damage of rock are interaction, but viscoelastic wave propagation in the rock and the damage of rock induced by the viscoelastic wave are usually investigated separately in the existing research and the coupled mechanism is difficultly clarified. The viscoelastic wave propagation in rock and the damage process of rock induced by viscoelastic wave propagation is investigated under the unified framework in this subject. Firstly, based on the dynamic stress-strain curve of artificial rocks with different viscosity coefficients measured during the split Hopkinson pressure bar tests, the viscoelastic constitutive equation and one-dimensional viscoelastic wave propagation model are established. The effect of viscosity coefficient on the stress wave propagation in the long artificial core is analyzed. Secondly, the influence of damage on the viscosity coefficient and the mechanism for the strain rate effect on the viscosity are clarified after the constitutive model of viscous damage is established and the one-dimensional wave propagation program is developed. Lastly, the mechanism for viscosity coefficient dominated by the joints of rock is clarified. The damage evolution of the rock induced by viscoelastic wave propagation and the effect of rock damage on the sequence viscoelastic wave propagation in the rock are investigated under different wave parameters. According to the above research, the coupled mechanism for the process of viscoelastic wave propagation and rock damage is clarified. This study may provide theoretical basis for the engineering problem such as the damage of surrounding rock mass subjected to blasting.

岩石中波传播表现出一定的黏性特性，岩石中黏弹性波传播和波传播引起的动态损伤是相互作用的过程，但当前普遍把两者视为两个独立的过程来研究，难以揭示两者之间相互作用机理。课题将黏弹性波的传播和岩石的动态损伤放在统一的框架下进行研究，首先，制备不同黏性参数的人造岩心，测试岩心的动态应力-应变曲线，建立黏弹性本构方程和一维黏弹性波传播模型，分析黏性系数对应力波传播规律的影响；其次，建立黏弹性损伤本构模型，开发一维波动分析程序，探讨损伤对黏性系数的影响，揭示黏性对应变率效应的影响机理；最后，探讨岩石中的缺陷对于黏性系数的影响，研究不同波形参数下黏弹性波诱致岩石损伤演化和岩石损伤程度对后续波传播规律的影响，揭示黏弹性波传播过程与岩石损伤过程之间的耦合机制，为解决爆破应力波诱发巷道围岩损伤等相关工程问题的研究提供理论基础。

在矿山开采、隧道开挖和水电站建设等岩体工程中，凿岩爆破技术广泛应用产生的爆破应力波会诱致岩石的损伤与破裂，岩体中原有的节理和岩石损伤破裂产生的新节理会导致爆破应力波的幅值衰减和波形弥散。岩石中黏弹性波传播和波传播引起的动态损伤是相互作用的过程，但当前普遍把两者视为两个独立的过程来研究，难以揭示两者之间相互作用机理。课题将黏弹性波的传播和岩石的动态损伤放在统一的框架下进行研究，首先，制备不同黏性参数的人造岩心，开展砂岩长杆和人造岩心长杆冲击试验，建立一维黏弹性波传播模型，分析黏性系数对应力波传播规律的影响；其次，建立黏弹性损伤本构模型，开发一维波动分析程序，研究不同波形参数下黏弹性波诱致岩石损伤演化和岩石损伤程度对后续波传播规律的影响，分析黏性对应变率效应的影响规律，揭示黏弹性波传播过程与岩石损伤过程之间的耦合机制；最后，基于一维应力波传播规律研究，揭示了全长黏结锚杆中应力波传播特性和含缺陷锚固锚杆中应力波传播特性，为现场锚固锚杆无损检测数据解译提供了理论支撑。基于上述研究为解决爆破应力波诱发巷道围岩损伤等相关工程问题的研究提供理论基础。