非整形試験片による岩石の引張り強さの迅速試験

抄録

Determination of the strength of rocks is very troublesome since it takes much time and effort to produce good test pieces. Therefore some methods for rapid determination of the strength of rocks are strongly demanded. The authors have investigated how to determine the strength of rock with irregular test pieces, i. e. rock pieces which are not machined. By theoretical as well as experimental study, they have obtained such a method to determine rapidly the tensile strength of rocks that an irregular test piece is crushed into two pieces by a concentrated loadF, the distance between the points of loading being 2α, and then the tensile strength of the rock is given by 1.4F, 2πα²