基于瞬态卸载诱发振动的深部硬岩工程原位三维扰动应力测试技术

This project focuses the research of in-situ test theory and method under three-dimensional disturbance of deep hard rock induced by transient unloading induced vibration. Based on theoretical derivation and numerical simulation, the vibration amplitude, frequency spectrum and space distribution property induced by transient unloading during deep hard rock excavation using drilling and blasting is studied, and an inverse model of geostress field based on induced vibration peak and main frequency is modeled. The in-situ test is carried out relying on the Jin-ping underground laboratory, identification and separation methods of signals induced by stress transient release based on blind source or wavelet analysis technology are established, the temporal and spatial distribution of rock stress under three-dimensional disturbance is proposed, as well as the three - dimensional perturbed geostress field testing method. This project conforms to the requirements of national major infrastructure projects, and the research results can provide a theoretical basis for the prediction and testing of rock stress under three-dimensional disturbance during construction of deep rock engineering.

本项目针对基于瞬态卸载诱发振动的深部硬岩三维扰动地应力场原位测试理论及方法开展探索性研究。利用理论推导和数值模拟方法，研究爆破过程中深部硬岩地应力瞬态卸载诱发岩体振动幅值、频谱及空间分布特性，建立基于诱发振动峰值和主频率的地应力场反演模型；依托锦屏地下实验室开展现场测试试验，建立基于盲源、小波分析等信号处理技术的地应力瞬态释放诱发信号的识别和分离方法，推演三维扰动下的围岩应力时空分布特性，提出三维初始/扰动地应力场测试方法。本项研究既符合国家深部工程建设的重大需求，又立足国际学术前沿，成果可为深部岩体工程安全评价及控制提供理论依据。

地应力是影响岩体稳定和工程安全的重要参数，应力变化将导致工程岩体变形、断裂，可能诱发岩爆、突发大变形等动力地质灾害。现有主流地应力测量技术都是基于钻孔内放置传感器的技术路线，国内外代表性技术有单向钻孔应力计、三向实心基体应力计、三向空心包体应力计和水压致裂法。这些技术未能实现对岩体中钻孔全长多点应力的测试，且传感器稳定性差，测试成本高，可重复性不理想。因此，方便快捷的地球物理力学方法可能成为地应力测试的选择。.本项目针对基于瞬态卸载诱发振动的深部硬岩三维扰动地应力场原位测试理论及方法开展探索性研究。首先通过研究深部硬岩的储能机理，从能量瞬态释放速率的角度揭示爆破过程中地应力瞬态卸载过程；其次，利用理论方法和数值模拟，研究爆破过程中深部硬岩地应力瞬态卸载诱发岩体振动幅值、频谱及空间分布特性，建立基于诱发振动峰值和主频率的地应力场反演模型；第三，建立基于盲源、小波分析等信号处理技术的地应力瞬态释放诱发振动信号的识别和分离方法，推演三维扰动下的围岩应力时空分布特性，提出三维初始/扰动地应力场测试方法；开展现场测试试验，验证所提出的三维应力进行反演测试方法。此项研究既符合国家基础工程建设的重大需求，又是深部岩体力学理论发展急需解决的关键科学问题。.结合项目研究，发表SCI、EI收录的论文4篇（另外接受和投出6篇），授权中国发明专利9项，受理1项；合著专著1部；培养研究生4名，项目负责人获湖北省杰出青年基金资助。研究成果在白鹤滩水电站坝基开挖、白鹤滩水电站调压室开挖、杨房沟水电站坝基开挖和陈台沟铁矿深埋巷道爆破开挖中得到推广应用，取得较好效果，项目获省部级技术发明或科技进步奖4项。