为了表征煤岩变形破坏规律，开展了煤岩试样单轴压缩试验；采用数字散斑观测系统获取表面应变场灰度图像，基于表面应变场灰度图像，计算灰度直方图并提取灰度特征参数，分析灰度演化特征，进而表征煤岩变形破坏特征。结果表明：根据试样表面裂纹出现的时间次序将其分为缓慢破坏型、瞬间破坏型和间隔破坏型；在煤岩破坏过程中，灰度直方图均呈现由高灰度向低灰度区域移动的趋势，不同破坏类型试样的灰度直方图波峰变化存在明显差异；灰度平滑度的变化能有效反映出裂隙的演化规律，灰度能量和灰度熵值反映煤岩变形破坏过程的复杂程度和破坏程度。

In order to characterize the deformation and failure law of coal rock, this paper carries out uniaxial compression tests of coal rock specimens, and obtains grey scale images of surface strain field by using digital speckle observation system. Based on the grey scale images of the surface strain field, the grey scale histogram was calculated and the grey scale parameters were extracted to analyze the grey scale evolution characteristics, and then characterize the deformation and damage of the coal rock. The results showed that the specimens were classified into slow failure, instantaneous failure and interval failure according to the time sequence of the appearance of cracks on the surface of the specimens. During the damage process, the grey scale histograms show a tendency to move from high grey level to low grey level, and there are obvious differences in the changes of the grey scale histogram wave peaks of the samples of different damage types; the change of grey scale smoothness can effectively reflect the evolution law of the fissure, while the grey scale energy and grey scale entropy reflect the complexity of the deformation and destruction process of the coal rock and the degree of destruction.