基于数字图像的岩石非均匀性表征技术及初步应用

DIGITAL IMAGE BASED CHARACTERIZATION METHOD OF ROCK'S HETEROGENEITY AND ITS PRIMARY APPLICATION

依据数字图像处理理论,研发出一种基于数字图像的岩石非均匀性表征技术。该技术描述的非均匀性更接近于岩石的真实非均匀性,并将其映射到有限元网格中,与原有的岩石破裂过程分析系统(RFPA)相结合,建立一种更能准确反映岩石细观结构的数值模型,从而弥补传统数值方法所采用统计理论表征岩石非均匀特性的不足。通过对2种常规试验(单轴压缩和单轴直接拉伸)的数值模拟,再现花岗岩试件在荷载作用下的真实破裂过程。数值模拟结果表明:岩石的细观结构对岩石的力学性能和破坏过程有重要影响。该方法为进一步研究岩石、混凝土等非均质材料的力学特性和破坏机制提供一种新的手段。

A digital image based characterization method of rock＇s heterogeneity is developed according to the theory of digital image processing.In the proposed method,digital image processing method is used as a measurement tool to represent the actual spatial distribution of different materials and components in the rock samples.The heterogeneity described by this method is approaching to the actual heterogeneity of rock,which is mapped into the grid of finite element method（FEM）.This characterization method is incorporated into rock failure process analysis（RFPA）code;and a numerical model that can actually reflect rock＇s heterogeneity is established,which overcomes the shortage that statistic theory is used to describe the heterogeneity of rock in traditional FEM.By simulating two regular laboratory tests（uniaxial compression and uniaxial tension tests）,real failure processes of granite are visually observed.The simulation results show that heterogeneity of rock has a great influence on its mechanical function and failure processes.This model provides an innovative method for the investigation on mechanical feature and failure mechanism of heterogeneous material such as rock,concrete and so on.