弱动力扰动触发型岩爆机理与定量化预测研究

Aiming at unclear mechanism and unpredictable problem of rockburst triggered by weak dynamic disturbance, which is a geological disaster phenomenon often encountered in deep tunnel during the excavation of intact hard-brittle rocks. Multi-level including material, structure-like and structure true-triaxial tests will be conducted using a new dynamic true-triaxial rockburst testing system to experimentally reproduce the rockburst under different couple static-dynamic stress conditions; by analyzing the temporal and spatial evolution of the energy and damage of hard rock during rockburst pregnant process, the mechanism of triggered rockburst induced by weak dynamic disturbance will be revealed. Then, according to the experimental results, constitutive model and strength criterion, which can reflect the damage, deterioration and ejection failure of high-stressed hard rock triggered by weak dynamic disturbance, will be established; the discrete element numerical simulation method for quantitatively predicting kinetic energy of ejected fragments will be proposed; the rockburst reproduced by physic test, as well as the rockburst under complicated stresses or boundary conditions, will be fine simulated to further reveal the mechanism and law of the studied rockburst. Finally, the proposed theories and methods will be verified and improved by engineering case study and application. It provides an effective way for quantitative prediction of rockburst induced by weak dynamic disturbance in deep rock engineering.

针对深埋隧洞工程完整硬脆性岩体开挖过程中常遇的弱动力扰动触发型岩爆地质灾害现象的机理不清与难以预测的问题，采用新型动真三轴岩爆试验系统，通过“材料-类结构-结构”等多层次真三轴试验，在室内再现不同动静组合加载条件下的岩爆过程，通过岩爆孕育过程中硬岩的能量与损伤时空演化特征分析揭示其发生机理；在建立反映弱动力扰动下高静应力硬岩损伤劣化和弹射破坏行为特点的本构模型与强度准则的基础上，提出此类岩爆弹射动能定量化预测的离散元数值模拟方法，由此实现岩爆物理试验过程的精细模拟，并推演复杂条件下岩爆过程，进一步揭示此类岩爆的发生机理与规律；最后通过工程实例与应用研究，验证并完善所提出的理论与方法，为深部岩体工程弱动力扰动触发型岩爆的定量化预测提供有效途径。

本项目针对深埋隧洞工程完整硬脆性岩体开挖过程中常遇的弱动力扰动触发型岩爆地质灾害现象的机理不清与难以预测的问题，采用新型动真三轴岩爆试验系统，通过“材料-类结构-结构”等多层次真三轴试验，在室内再现了不同动静组合加载条件下的弱动力扰动触发型岩爆过程，获得了此类岩爆复杂孕育过程的科学数据；通过岩爆孕育过程中硬岩的能量与损伤时空演化特征分析，结合声发射监测数据分析，揭示了此类岩爆的孕育机理；结合室内试验与现场工程应用效果反馈，提出了此类岩爆发生的风险、位置、范围与强度预测的离散元与近场动力学数值模拟方法，为深部岩体工程弱动力扰动触发型岩爆的定量化合理预测提供了有效途径。