水封洞库裂隙岩体渗流力学特性研究

Study on the Mechanical Characteristics of Seepage in Fractured Rock Mass of Water Sealed Cave Reservoir

摘要: 天然岩体由于裂隙的存在，渗透性具有明显的各向异性，研究裂隙岩体的渗透特性对准确刻画库区渗流场特征、保证洞室水封性具有重要意义。以宁波某地下水封洞库主洞室裂隙岩体裂隙特征统计数据为基础，分析得到优势裂隙组各项特征，应用Monte-Carlo随机模拟技术生成二维离散裂隙网络(DFN)模型，并计算得到不同尺寸试样的等效渗透系数。结果表明：试样尺寸达到110 m × 110 m后，试样可等同于连续介质，此时的试样为裂隙岩体渗流表征单元体(REV)。

Abstract: Due to the presence of fractures, natural rock masses exhibit significant anisotropy in permeability. Studying the permeability characteristics of fractured rock masses is of great significance for accurately characterizing the characteristics of the seepage field in the reservoir area and ensuring the water sealing of caverns. Based on the statistical data of rock fracture characteristics in the main chamber of a groundwater sealed reservoir in Ningbo, various characteristics of dominant fracture groups were analyzed. Monte-Carlo random simulation technology was applied to generate a two-dimensional discrete fracture network (DFN) model, and the equivalent permeability coefficients of samples of different sizes were calculated. The results show that when the sample size reaches 110 m × 110 m, the sample can be equated to the continuous medium, and the sample is the fractured rock seepage characterization unit (REV).