煤岩破裂过程表面电位云图软件开发及应用

针对克里金插值法中理论变异函数拟合精度不稳定及缺乏专用电位云图软件问题,提出了计算理论变异函数模型参数的自动-人工拟合方法,并利用MATLAB开发了煤岩破裂过程表面电位云图软件。对预制45°裂纹岩样进行了单轴压缩实验,利用该软件绘制了岩样变形破裂过程中的表面电位云图,分析了表面电位分布与试样破裂状态的对应关系。研究表明:自动-人工拟合法计算过程稳定,有效提高了克里金插值法的精度;基于开发的电位云图软件绘制的电位云图能够真实反映煤岩体的表面电位分布及变化;岩样表面电位云图可以反映裂纹的扩展方向及岩样破裂状态;在岩样弹性变形阶段后期,表面电位云图反映了岩样裂纹扩展的前兆信息。

Development and application of surface potential nephogram software for coal and rock failure process

The fitting precision of theoretical variogram is unstable for the Kriging interpolation method,and there is lack of special potential nephogram software for coal and rock failure process.To overcome the problem above,an automatic-manual fitting method was proposed to calculate theoretical variogram model parameters in Kriging interpolation method,and a surface potential nephogram software for coal and rock failure process was developed by using MATLAB.The software was used to draw surface potential nephogram during the process of uniaxial-compression for the rock samples 45° precrack.The corresponding relationship of surface potential and rupture state was analyzed.The results show that the computing process of the automatic-manual fitting method is stable,and the precision of Kriging interpolation method is effectively improved.The distribution and change of surface potential of coal and rock can be truly reflected by the surface potential nephogram.The fracture propagation and state of the samples can be reflected by the surface potential nephogram as well.During the late elastic deformation stage of the sample,the surface potential nephogram can be served as the precursory information of the crack propagation.The study results can be used to assess the stability of coal and rock.