期刊名称：IOP Conference Series: Earth and Environmental Science
印刷版ISSN：1755-1307
电子版ISSN：1755-1315
出版年度：2020
卷号：570
期号：2
DOI：10.1088/1755-1315/570/2/022030
语种：English
出版社：IOP Publishing
摘要：The laboratory tests and the numerical simulation of the particle flow code of triaxial compression are conducted to analyze the fractal dimensions of fracture surface, strength properties, energy dissipation, damage patterns, and crack evolution. The following results are obtained. (1) Under low confining pressure, the fracture surface of a brittle specimen is rough, and the angle relative to the maximum principal stress is small. The specimen eventually exhibits a local tensile–shear failure mode. As the confining pressure increases, the strength of the specimen increases, and the yield platform for the stress–strain curve is more obvious. The main fracture surface flattens, and the fracture angle increases as the confining pressure increases. The specimen macroscopically exhibits a shear failure mode. (2) As the confining pressure increases, the trend of transgranular shear failure becomes obvious, and the microfracture surface has a smaller fractal dimension. (3) In the triaxial compression test, energy is stored, dissipated, and released. When the storage limit is reached, the internal elastic strain energy becomes released sharply, and the damage variable increases rapidly. (4) As the confining pressure increases, the number of tensile and shear cracks accumulates in an "S" shape, and the proportion of shear cracks increases gradually.
