Experimental and numerical study on splitting failure of brittle solids containing single pore under uniaxial compression

Under uniaxial compression, brittle solids are frequently observed to fail by splitting parallel to the direction of loading. Although this failure has long been recognized, considerable confusion regarding how such splitting mechanisms develops still remains. Axial propagation of a crack-like flaw inclined to the loading direction of compression is one of the accepted mechanisms. In this paper, the axial propagation of a pore-like flaw as one of the mechanisms of splitting failure is approached. A series of physical and numerical tests of uniaxial compression on samples containing a single hole with varied diameters and sample widths are carried out to investigate the splitting failure, the failure modes and strength characterization due to crack growth from such flaw. Samples made from the Hong Kong granite are used in the physical tests to study the inference of heterogeneity of solid on crack growth. A Material Failure Process Analysis code (MFPA2D) is used as a numerical simulation tool to compare and explain the mode of failure from experiment. Sammis and Ashby [Sammis, C.G., Ashby M.F., 1986. The failure of brittle porous solids under compressive stress states. Acta Metall. 34, 511–526] theoretical crack model is employed to study the inference of sample size and diameter of hole on peak strength.