将数字图像技术与Munjiza提出的有限元法-离散元法(FDEM)耦合分析方法结合,研制了可表征岩石真实非均质性的 FDEM 分析系统,为从细观角度对岩体进行建模以及研究岩体的破裂机制提供了新途径。该系统借助数字图像技术从岩石断面的图像获取岩石材料的真实细观结构,借助成熟的网格剖分技术,将其映射到 FDEM 计算网格中,从而克服了原有 FDEM 在考虑材料非均质性所存在的不足。利用该系统,进行了巴西圆盘劈裂试验的数值模拟,再现了花岗岩在荷载作用下的真实破裂过程。数值模拟结果表明,考虑非均质性的岩样应力分布呈现出非对称性,岩石的细观结构对岩石中裂纹的扩展及应力分布有重要影响。
Based on the digital image technology and FDEM (combined finite-discrete element method) proposed by Munjiza, the FDEM system is developed, which can identify the interface of different materials from a rock-like cross section photo. This system provides an innovative method for the investigation on mechanical feature and failure mechanism of heterogeneous material such as rock and so on. The system using digital imaging technology acquisition of real rock material microstructure from the rock section of the image, meshing with mature technology, mapped into FDEM computing grid, thus the deficiencies of the original FDEM in considering the material heterogeneity are overcomed. Using this system, conducting numerical simulations of the Brazil split test, real failure processes of granite are visually observed. The simulation results show that, considering the heterogeneity of rock samples exhibiting asymmetric stress distribution, rock microstructure has an important influence on stress distribution and cracks of rock.