To analyze the fracture coalescence behavior of rock, rectangular plastic marble specimens 150mm×150mm×15mm containing single fissure were tested under uniaxial compression. Based on the experimental results of affecting many factors, the influence of non-straight fissure("S") geometry and different fillings on the strength and deformation behavior of brittle marble samples is analyzed in detail. Compared with different fissure angle, crack length, and different fillings, The sensitivity of strength parameters on the marble containing single fissure from big to small can be arrangement as following: fissure fillings > fissure angle > fissure length. The crack resistant ability of rock mass varied with different fillers, the cohesive force and strength of cement paste were much better than gypsum, which indicated that cement paste had a nice reinforcement paste efficacy. Compared with previous studies, it is similar with the straight fissures and the non-straight fissures on the damage characteristics no matter fillings or no fillings, which all observed from upper and under tips of fissure along the vertical direction and gradually departs towards the direction of axial stress. However, the wing crack angle is difference between the straight fissure and the non-straight fissure, the average crack angle of straight fissure ("/" type) is 70°, but the average crack angle of non-straight fissure ("S" type) is 40°. When changing different angle (α = 15°, 30°, 45°, 60°, 75°) containing no filling single fissures, it is clear that angle 75° is easier to broken during the loading for marble rock material. The present research is helpful to understand the failure behavior and summarized the crack extension mode with fillings materials of engineering rock mass, such as deep underground excavated tunnels.
|Journal||Electronic Journal of Geotechnical Engineering|
|Publication status||Published - 2015|