A Direct Measurement Method for the Uniaxial Tensile Strength of Rock

A universally applicable direct tension test method is proposed in this paper based on the concept of “compression-to-tension”. Using this method, one or two typical rocks were selected for each of the three types of rocks. The testing results of the direct tension method proposed were compared with the internationally recommended Brazilian splitting method to validate the feasibility of the direct tension method. Results showed that the tensile strengths of six typical rocks were consistent using the direct tensile test method proposed in this study and the Brazilian splitting method recommended internationally. The direct tensile strength deviation coefficient (Cv) of the six types of rocks was less than 0.1, indicating very small variability. In this study, the deviation coefficient (Cv) of the axial displacement corresponding to the tensile strength in both the direct tensile and indirect tensile tests was also less than 0.1, reflecting minimal variability. This shows the consistency of the two tensile test results to a certain extent, and also shows that the direct tensile test method is feasible to determine the tensile strength of rock.