International Journal of Rock Mechanics and Mining Sciences & Geomechanics Abstracts
On the validity of the ‘Brazilian’ test for brittle materials
Abstract
Failure in the Brazilian tensile test (diametral compression of a disc) is analysed on the basis of a Griffith-type fracture criterion, empirically generalised for an arbitrary ratio between uniaxial compressive strength and uniaxial tensile strength. Results indicate that failure may occur away from the centre of the test disc for small angles of loading contact area with materials of low compression-tension ratios. In such cases the ‘tensile strength’ as usually calculated from test results, is lower than the true value.
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