深部工程锚固体应力渗流耦合流变时效特性的试验研究及机理分析

Major infrastructure and energy development are promoting at an unprecedented rate in China. The deep geology conditions including high stress, high osmotic pressure and more fields coupling greatly affect the engineering properties with engineering depth evolution. In the project, the bolted rock mass of deep engineering looks as the research object, and the aging mechanics characteristics of anchored rock mass, the time-space performance evolution law of deep engineering with time are researched using rock damage mechanics, fluid mechanics, rheology, electrochemical, system engineering theory. The geological properties and engineering characteristics of deep rock are studied through the field investigation. The aging mechanics characteristics of rock mass and anchorage body are researched through the indoor experiment. The space-time evolution law of deep engineering is studied using multi-source information integration and syncretic analysis method. The focuses are centralized on laboratory physical model test of bolted body aging mechanics characteristics using real-time monitoring technology such as electrochemical impedance spectroscopy techniques and pre-buried strain gauge, and the time-space performance evolution models of deep engineering are obtained using methods of numerical analysis and expert system based on the constitutive relation coming from the experiment. The academic ideas of deep engineering aging performance evolution with macro mesoscopic dynamics mechanism and the deep engineering safety control throughout the engineering design, construction, operation and decommissioning would realized.

我国重大基础设施及能源开发以前所未有的速度在全国展开，大型地下洞室及矿产资源开采也较快地向深部延伸，高应力、高渗透压及多场耦合等环境条件极大影响着深部工程的长期安全稳定。本项目以深部工程锚固岩体为研究对象，运用岩体力学、流变学、电化学、系统工程等理论，研究在应力渗流耦合作用下，锚固岩体的时效力学特征，深部锚固工程的时空性能演化。通过现场调查研究复杂条件下深部岩石的地质属性和工程性能，室内试验研究岩体和锚固体的时效力学特性，多源信息集成与融合分析方法研究深部锚固工程的时空演化规律。重点是利用电化学阻抗谱、预埋应变片等技术实时检测锚固岩体应力渗流耦合作用下时效性能演化的室内物理模拟试验；基于室内试验得出的本构关系，利用数值分析和专家系统分析深部锚固工程时空性能演化模型。为最终实现深部工程时效性能演化的宏细观力学机制，为深部岩石工程安全评估及灾害预警预报服务。

随着城市立体化以及深部能源开采的大力发展，锚固体系在岩石工程的应用愈来愈广泛，同时服役期限也愈来愈长。本项目以岩石工程锚固体系为研究对象，重点研究了岩石工程服役期间多场耦合条件下锚固体系随时间的力学行为。首先，进行了岩体内部应变检测技术研究，重点是采用直角式三维接触应变花，进行了基于相似材料的预埋应变技术的试验研究及理论分析；接着，进行了岩石锚固体系的结构效应以及岩石锚固体系的时效特征研究。其中的重点内容有两项，一是新技术在岩石锚固体系变形特征检测方面的应用，这些技术包括：基于数字图像相关方法的应变观测，裂网的电化学实时检测，以及基于数模转化的层状岩石水力压裂裂网特征评价方法。二是研究了渗流、水力和应力耦合作用下的岩石工程锚固体系的力学行为，尤其是长期强度特征。最后，在室内试验基础上，利用数值分析手段研究了深部锚固工程时空性能演化规律。同时开发了既有锚固工程的加固处理技术。本项目开发的技术以及研究的理论成果，能够为复杂岩石工程全生命周期内的安全评估及灾害预警预报提供借鉴。