Abstract
This paper presents the experimental results of a laboratory point load testing program carried out to analyze the effect of two different point load mean value calculation procedures on the prediction accuracy of uniaxial compressive strength of rocks. Apart from the calculation procedure corresponding to the one suggested by ASTM and ISRM, a second calculation procedure involving the ordinary arithmetic mean value was used in the analyses. Axial point load tests were conducted on a total of 19 rocks having two different thickness-to-diameter ratios. Finally, the results of the point load tests were correlated with those of the standard uniaxial compressive strength tests, and some test statistics were employed to determine the relative effectiveness of the considered calculation procedures. Valid for axial testing method and the tested rock types, it was concluded that the suggested mean value calculation procedure by the ASTM and ISRM has no significant advantage compared with the traditional statistical procedure that involves ordinary arithmetic mean.
