裂隙岩体注浆驱替渗透诱发劈裂裂隙演化机理研究

In this research, as an attempt to improve the existing problems of propagation law and monitoring method for splitting cracks induced by grouting displacement and permeability in fractured rock mass, the physical tests (including laboratory tests, microseism industrial test in grouting project sites) , numerical simulation and mathematical theoretical analysis are employed to carry out the above research. The wave velocity, physical and mechanical parameters of rock specimens with natural cracks will be obtained by means of electro-hydraulic servo testing machine, universal testing machine and wave velocity measuring instrument. Using the following measures of acoustic emission, dye tracing method, high-speed camera and high-definition endoscope, a three-dimensional similar material simulation experiment system of grouting process will be designed and built up independently to reveal the fracture distribution and its space-time propagation characteristics in the process of displacement, permeability and splitting, then the numerical model of practical project will be constructed really to discover the corresponding representation relation between splitting cracks and source size of acoustic emission. Subsequently, the full-scale grouting project in-site test will be started timely to reveal three-dimensional real time and dynamic propagation law of fracture in the whole process of splitting by the high precision microseismic monitoring system, at the same time, the mutual feedback model among characteristics of rock mass structure, grouting parameters and fracture evolution will be established combining with similar simulation experiment. Eventually, a new monitoring and imaging method will be put forward to monitor dynamically and real-timely the fracture shape of splitting process based on mathematical statistics algorithm and 3D data analysis system, which will optimize primely the in-site grouting engineering. It is expected that the research result could provide some theoretical guides for the design and evaluation of grouting engineering for rock mass.

针对裂隙岩体注浆驱替渗透诱发劈裂裂隙扩展规律及监测方法研究存在的问题，本课题拟通过实验研究（相似模拟实验、注浆工程现场试验）、数值模拟及数理算法相结合的方式，借助于电液伺服试验机、电子万能试验机及波速测试仪，获得天然含裂隙岩样的波速和物理力学参数。自主搭建注浆过程三维相似材料模拟实验系统，运用声发射、染色示踪、高速摄像仪及高清内窥镜等手段，揭示驱替渗透和劈裂期间裂隙分布及时空扩展规律，通过构建依托实际工程的数值模型，探寻劈裂裂隙与声发射源尺寸的对应表征关系。采用高精度微震监测系统，开展全尺度的注浆工程现场试验，获得劈裂“全过程”三维实时动态裂隙扩展规律，并结合相似模拟实验，建立岩体结构特征、注浆参数及裂隙演化的互馈模型。在数理统计算法及三维数据分析系统的基础上，提出基于微震数据的裂隙成像方法，实时动态地监测识别劈裂裂隙形态，优化现场注浆工程。尝试为岩体注浆工程的设计与效果评价提供理论依据。

针对裂隙岩体注浆驱替渗透诱发劈裂裂隙扩展规律及监测方法研究存在的问题，本课题通过实验研究（相似模拟实验、注浆工程现场试验）、数值模拟及数理算法相结合的方式，借助于电液伺服试验机、电子万能试验机及波速测试仪，获得天然含裂隙岩样的波速和物理力学参数。自主搭建注浆过程三维相似材料模拟实验系统，运用声发射、染色示踪等手段，揭示驱替渗透和劈裂期间裂隙分布及时空扩展规律，通过构建依托实际工程的数值模型，探寻劈裂裂隙与声发射源尺寸的对应表征关系。发现预制裂隙与注浆孔不相交时，含预制裂隙的煤岩相似试样注浆劈裂裂隙的发育过程包含劈裂贯通、浆液填充、裂隙劈裂、劈裂扩展四个阶段；随着预制裂隙尺寸的增大，劈裂裂隙越易向着预制裂隙的方向发育；与预制裂隙贯通后，新发育的劈裂裂隙更倾向沿着预制裂隙的角度向外扩展；相交时，无劈裂贯通阶段。预制裂隙位置、角度和尺寸影响甚至决定着劈裂裂隙的发育方向，围压影响注浆劈裂裂隙的起裂压裂及岩体失稳压力。