截齿截割煤体变形破坏过程的散斑测试研究

采用白光数字散斑相关测定方法，在压力机上，在截割模拟实验台上分别对煤试件进行刀齿、镐齿的截割实验，研究被截割煤体的变形破坏过程。研究表明：截齿截割煤体过程中，煤体出现稳定的变形局部化带，且最终发展为宏观裂纹；煤体变形局部化带为一个倾斜带；刀齿截割时，变形局部化发展较慢，但产生变形局部化后，局部化带宽且带内应变值较高；而镐齿截割时，变形局部化发展较快，但产生局部化后，局部化带窄且带内应变值不如刀齿高。截齿截割作用下的煤体变形破坏主要是剪破坏。

Study on deformation and destruction course of coal body under function of pick cutting with digital speckle correlation method

Based on the cutting experiments used by cutter tooth and point-attack pick on the press and cutting simulation test table, the deformation and failure process of coal body are studied by the method of white light digital speckle correlation. The results indicate that a stable deformation localization band occurs in the coal cutting course and develops to macroscopic crack; the deformation localization band is slantwise; while the cutter tooth is used, the deformation localization develops slowly, and the localization becomes wider and the strain value in the band area higher afterwards; when the point-attack pick used the localization develops quickly and the localization band becomes narrow and the strain value in the band lower. Finally, the authors draw a conclusion that the main failure of coal body is shear failure under the action of cutting.