基于CT扫描的花岗岩三维数值试件重构模型及应用

岩石细观结构控制宏观破裂模式,建立一种表征岩石细观结构的数值模型重构方法并能够嵌入到力学模型中计算岩石破坏过程应力分布,对于揭示岩石破坏机理具有重要的理论意义.论文以花岗岩试件为研究对象,借助于先进的CT技术获取试件内部结构切片图像,利用数字图像处理技术实现了基于CT图像的花岗岩试件结构的识别和表征,基于矢量化方法和岩石破裂过程分析系统RFPA3D建立了花岗岩三维数值试件,对花岗岩试件单轴压缩破裂过程进行了数值模拟.通过数值试验结果与物理实验结果对比发现,基于CT扫描的花岗岩数值试件真实表征了岩石细观结构,所以力学模拟得到的破裂模式与室内物理实验得到的破裂模式相似,同时能够解译岩石破裂力学机理,为深入研究岩石、复合材料等力学特征提供了一种可行方法.

THE 3D NUMERICAL SPECIMEN OF GRANITE BASED ON CT TECHNOLOGY AND APPLICATION

Based on the theory that the rock failure model is ar esult of microscopic structure,the numerical model obtained by embedding the microscopic structure into the mechanics model to calculate the stress distribution is built to reveal the unstability in the loading process.The granite specimen is taken as an example,and the computerized tomography (CT) technology is employed to capture a series of sectional images of the granite specimen.Then the identification and characterization of granite specimen structure based on the CT image are achieved by the self-developed digital image processing technology.By means of the image vectorization method and 3D Rock Failure Process Analysis (RFPA3D),a 3D numerical model for the granite specimen is reconstructed,and the numerical specimen is further used for the uniaxial compression.By comparing the simulation results w1th the experimental ones,it is found that the numerical specimen of the CT images well characterizes the granite microscopic structure,and the results obtained from the numerical failure model agree with the experiment data.The numerical specimen based on the CT technology provides a feasible method for deeply explaining and studying the mechanical characteristics of rock and composite materials.