截齿截割煤体变形破坏过程数值模拟研究

采用应变软化的模型,使用连续介质快速拉格朗日分析法(FLAC,FastLagrangianAnaly-sisofContinue)进行数值模拟计算;研究截齿截割作用下煤体变形破坏过程;分析各种工况下不同参数对煤体塑性区、最大位移、最大主应力、最大剪应力的影响。研究表明:截割力与塑性区大小成正比,位移、剪应力、主应力随截割力增大而增大;截深与塑性区大小成反比;截割角度与塑性区面积关系密切,试验用煤体最佳截割角度为5°左右;截割速度增加,塑性区面积减小;通过分析截割动态过程,得到位移矢量图及剪应变等值线图,发现截割过程中煤体的破坏是拉、剪联合作用的结果,以剪破坏为主。

Research on Numerical Calculation of Deformation and Destruction Course of Coal Body under the Function of Pick Cutting

By adopting strain intenerated model and using numerical calculation of FLAC(Fast Lagrangian Analysis of Continue), deformation and destruction course under pick cutting is researched, different parameters' great influence on plasticity district, max displacement, max main stress and max shearing stress under the various kinds of operating modes is analyzed. Study shows that the cutting force is basically direct ratio to the size of plasticity district, which causes max displacement, max main stress and max shearing stress to increase with the cutting force; that cutting depth has an inverse ratio to the size of plasticity district, and that cutting angle has a close relation with the size of plasticity district. For the experimental coal body material, the best cutting angle is about 5 degree. The area of plasticity district will decrease with the increasing of cutting speed. Through analyzing the dynamic course, the displacement vector graph and shear strain contour line graph have been obtained. From which it is found that destruction of coal body is the joint function of tension strain, shearing strain and compression strain, but mainly shearing strain.