【摘要】 以三峡花岗岩为例,利用有限差分程序FLAC进行非均质岩石材料的破坏过程模拟。首先,利用花岗岩微观结构观测图像确定数值模拟计算网格的合适尺寸;进一步结合花岗岩的矿物鉴定结果,在数字图像处理的基础上,利用模糊C均值聚类方法,实现了数值计算模型与材料真实细观结构的耦合分析,形成了一套较完整的、更加方便快捷的非均质岩石材料数字图像处理技术。在此基础上,利用同批次三峡花岗岩的经验应变软化模型,进行了单轴抗压下岩石的剪切带分布及裂纹破坏过程模拟,对破坏过程中的应力集中现象进行了探讨。最后,围绕该花岗岩岩样进行了不同围压三轴压缩的数值仿真研究,得到了一些有益的结论,同时也表明,在岩石破裂过程数值模拟分析中引入数字图像处理技术是岩石细观结构破坏力学行为研究的一种方便而有效的方法。更多还原

【Abstract】 For the Three Gorges granite,a finite difference software package FLAC is used to study failure process of heterogeneous rock material.Firstly,proper scale of finite difference grids is under consideration with scanning electron microscopy photo of the granite.Based on mineral components identification results of the granite and fuzzy clustering method,the actual image data are transformed into the finite difference grid by applying image processing techniques.A convenient and efficient two-dimensional numerical modeling method for heterogeneous geomaterials is presented.Furthermore,shear bond propagation and failure process of the granite are simulated in uniaxial compression test based on experimental strain soft model;and stress concentration phenomena are analyzed.Finally,numerical simulation of granite samples under different triaxial compression tests is studied.The results show that the numerical modeling method based on digital image processing can be used to calculate the mechanical responses of geomaterials by taking their heterogeneities into considerations.更多还原