How to Measure the Tensile Strength of Rocks

How to Measure the Tensile Strength of Rocks

Principle and equipment are the same as for the test for tensile strength of hydraulic-cement mortar. The test specimen has the shape of a briquet. While in the original cement mortar test the briquet is cast in a special mold, it is prepared from rocks in different ways, depending on how easily they can be cut and shaped.

Soft rocks, which cannot be core-drilled with a carboloy or diamond bit, are simply hand-cut. Only two dimensions need be watched. The first is the 1-in. diam at the narrowest cross-section of the briquet. The other critical measure is the radius of curvature of the waistline, as the roller supports in the grips have a fixed distance.

Hard rocks, limestones, igneous, and metamorphic rocks can only be diamond-drilled or diamond-cut. Here the method of getting the tension briquets by accurate placing of EX-drill holes is especially economical.



measuring the tensile strength of rocks