Summary of the Transformational Relationship between Point Load Strength Index and Uniaxial Compressive Strength of Rocks

Abstract

The point load test is an effective and rapid way to predict rock strength. Regarding the investigation of point load strength and the failure characteristics of rock, the point load test’s advantages and application scopes are introduced in this paper. According to the three main components—the rock itself, the size effect, and the loading cross-sectional area—the point load strength’s influencing factors and mechanisms on rock failure were analyzed, followed by expounding the significant effect of the technology of the point load test on evaluating engineering safety and stability. Based on previous scholars’ research results, there is a strong correlation between the point load strength and the uniaxial compressive strength. The parameters of the rocks from different regions and different sediments were summarized via substantial field and indoor testing. The functional relationship (mainly including the linear function, quadratic function, exponential function, power function, and logarithmic function) between the point load strength and the uniaxial compressive strength was obtained by mathematical statistical analysis. Finally, the challenges regarding the point load test were discussed, and accordingly, suggestions for future research were provided.