应变型岩爆的弹射动能释放机理与定量化预测方法研究

This project is going to study the release mechanism and quantitative prediction methods of ejection kinetic energy for strain rockburst by using methods including experimental study, theoretical analysis, numerical simulation and engineering practice in combination. Through true triaxial rock mechanics experiment of unloading one-side and exposing one free face, the process of ejection damage of rockburst under different loading or unloading conditions, the energy evolvement process are obtained by quantitative test for releave the release mechanism of ejection kinetic energy; Then, we establish a constitutive model reflecting strength degradation and discontinuous deformation of of hard rock to propose a quantitativly predictive method based on distinct element numercial simulation. Based on intelligent optimization back analysis of constitutive model parameters, physical test process by fine numerical simulation is achieved. Thus, the rockburst process under complicated conditions are deduced by numerical simulation for releave the release mechanism of ejection kinetic energy. Finally, the proposed theories and methods are verified and improved by cases back-analysis and engineering application. The reserch results will pave a effective ways for quantitative prediction of ejection kinetic energy of strain rockburst in deep underground rock mass engineering.

本项目采用试验研究、理论分析、数值模拟与工程实践有机结合的方法，系统开展应变型岩爆的弹射动能释放机理与定量化预测方法研究。通过真三轴单面突然卸载且暴露临空面的岩石力学试验，模拟不同加卸载条件下应变型岩爆的弹射破坏过程，定量化测试其中的能量演化过程，探索岩爆弹射破坏的动能释放机理；通过建立反映硬岩峰后强度劣化和弹射破坏非连续变形行为特点的本构模型，提出岩爆弹射动能定量化预测的离散元数值模拟方法，进而在本构模型参数智能优化反分析的基础上，实现岩爆物理试验过程的精细数值模拟，并推演复杂条件下的岩爆弹射破坏过程，进一步揭示岩爆的弹射动能释放机理；最后，通过工程岩爆实例反分析，结合工程应用研究，验证和完善所提出的理论与方法，为深部地下岩体工程应变型岩爆弹射动能的定量化预测提供有效途径。

本项目针对深部工程中岩爆地质灾害难以准确预测的问题，采用自主研发的真三轴岩爆试验系统，通过系统地开展应变型岩爆试验，结合应力、应变、声信号、弹射速度等物理量定量化测试，发现了三向应力、支护力与温度变化对岩爆弹射动能的影响规律，进而在阐明岩爆能量演化过程的基础上，深入揭示了岩爆弹射动能释放机理；建立了反映峰后强度劣化和弹射破坏非连续变形特点的硬岩本构模型，提出了岩爆弹射过程的离散元数值模拟方法，实现了岩爆发生的位置、范围与过程的精细数值模拟；在岩爆声信号前兆特征与演化规律若干发现的基础上，提出了基于声信号的岩爆动态预警方法。项目研究成果克服了传统定性化预测方法的局限性，为深部岩体工程应变型岩爆弹射动能的定量化预测提供了有效途径，为深部硬岩工程的设计规范制订与施工安全提供了科学依据与技术支撑。