坝基裂隙岩体三维灌浆数值模拟

坝基灌浆工程地质条件复杂且具有隐蔽性，如何建立能准确反映岩体内裂隙分布情况的三维随机裂隙网络模型，并进行浆液扩散特征的研究是灌浆数值模拟的关键和难点。现有研究大多通过岩体揭露面统计资料估计裂隙的几何参数，无法有效反映复杂裂隙真实特征，且灌浆模拟研究中多将裂隙简化为单一裂隙或规则裂隙网络。本文采用Monte Carlo法建立三维随机裂隙网络模型；提出三维裂隙宾汉姆流体灌浆数学模型，实现对随机裂隙内宾汉姆浆液扩散特征的研究；运用该模型对某水电站坝基裂隙岩体灌浆过程进行模拟，结果表明：浆液主要在与灌浆孔相交的裂隙内流动，灌浆压力在灌浆孔附近衰减速率最快且对浆液扩散的影响较为显著。同传统裂隙灌浆模拟相比，该方法能有效反映复杂裂隙的真实特征，获取更贴近实际工程的灌浆结果，为保障灌浆工程的安全建设和经济合理性提供了理论依据。

Three-dimensional grouting simulation in fractured rock mass of the dam bedrock

It is important to have a good understanding of the accuracy of 3D fracture network model and the spread process of the grouting. Current 3D geological model are not efficient and cost-effective in visual-izing complex fracture distribution for grouting simulation. Researches on grouting simulation simplified the stochastic fracture as one planar fracture or regular fracture network. To solve the above problems,the Car-lo Monte method is adopted and a 3D stochastic fracture network model is established. Considering Bing-ham fluid characteristic, a three-dimensional grouting model is proposed. The bedrock curtain grouting of a hydropower station is taken as a case. The results show that the grout almost flows in the fractures that pass through the borehole,and grouting pressure decreases the fastest near the borehole and affects the dif-fusion markedly. Compared with the traditional results, this method can not only reveal the actual fractures features,but also obtain more reliable simulation results,which provides a reliable theoretical basis for engi-neering safety and economic efficiency.