3.2 Types of Test Methods
3.2 Types of Test Methods
3.2.1 Loading
A number of rock strength tests have been developed which apply a known load to a specimen of fixed geometry. There are a number of ways in which a force can be applied to a body depending on the geometry of a test piece, which can range from irregular lumps to highly machined complex geometric shapes. There are several different designs for the method by which a load is applied to the test piece, from points to flat surfaces. In a typical test the load at which breakage occurs is correlated to the material strength. Loading tests that give a measure of tensile strength have been shown to correlate well with comminution energy requirements [Bearman 1989, 1997]. A typical example of a test that produces a tensile strength parameter is the Brazilian test in which, although the test piece is loaded in compression, causes the sample to break in tension due to the biaxial loading applied in the procedure.