Ge-Row data of deformation localization of raw coal and briquette coal

To compare and analyze the difference in deformation and damage law of soft and hard porous media materials, the digital image correlation is used to evaluate the heterogeneous development of strain fields of hard and brittle raw coal and soft plastic briquette coal materials under uniaxial compression. Through the defined statistical indexes, the quantitative characterization of deformation localization is realized, and the material damage constitutive model based on the statistical indexes of strain field is established. The results show that the yield stage of raw coal is not obvious, showing the characteristics of strain hardening and X-shaped macroscopic shear failure. The yield stage of briquette coal is more obvious, showing the characteristics of strain softening and a tensile failure mode. The progress of strain localization can well reflect the damage and destruction process of materials. The progress of strain localization of briquette coal can be divided into uniform deformation stage, localization stage and failure stage, while the stage characteristics of localized evolution of raw coal is not obvious. The theoretical results of the damage constitutive model defined by statistical indexes are in good agreement with the experimental data, which well reflect the stress and strain characteristics of the two materials