An assessment of a technique for determining the tensile strength of rock

The reliability of the diametrical compression of a disk with a small central hole as a technique for determining the tensile strength of rock is described. Experiments on rock and plaster show that failure occurs in tension and that the tensile strength is dependent upon the disk dimensions. Some justification is given for the application of elasticity theory to rock. It is suggested that the disk dimensions should be standardized if the test is to be used as a routine method of determining the tensile strength of rock.