非均质岩体压缩破坏的数字图像相关研究

通过实验研究了某大型水利工程现场花岗岩,在其岩体局部存在显著非均质情况下,非均质性对岩体的抗压强度和变形场分布的影响。变形场的测量采用数字图像相关(Digital Image Correlation, DIC)方法。花岗岩表面细观形貌存在较好的灰度差异,可以作为DIC方法的自然散斑图。对比非均质岩体与均质岩体两个试样的测试结果发现:花岗岩中夹杂的弱质岩体大大降低了岩石的整体抗压强度,弱质岩体的破坏诱发了岩石的整体失稳破坏。两种不同特性岩体的分布情况会引起整体位移场分布的变化。在两类岩体的边界存在较明显的剪切作用。因为非均质岩体边界混合层的强度并不低,所以这种剪切作用不一定产生剪切破坏。但如果在边界层出有明显缺陷,该剪切作用就可能会引发致命破坏。

Digital Image Correlation Study on Damage of Heterogeneous Rock under Compression Loading

Experimental study was carried out for researching the compressive strength and deformation field on heterogeneous granite rock exploited from the site of a large hydraulic project.Digital Image Correlation(DIC)method was used to measuring deformation field on the surface of rock.As natural speckles,the exposed meso-surfaces with good gray levels were captured by high resolution CCD.Comparing the heterogeneous and homogeneous rock,the compressive strength of heterogeneous rock was obviously reduced by weak ...