Position and Load of Failure in Brazilian Test; A Numerical Analysis by Griffith Criterion

Abstract

Failure in the Brazilian test (diametral compression of a disc) has been numerically analyzed on the basis of the Griffith fracture criterion. The analysis indicates that the angle subtended by the loaded arc strongly affects the position and the load of failure. Failure occurs away from the center of the disc for small angles, but it initiates at the center for the angle over a certain degree. The load of failure increases with increasing angle, and the derivative of the load against angle changes abruptly at that certain angle. These results agree with the experimental studies performed by others. It is erroneous to calculate the splitting tensile strength as p/πRL without respect to the angle subtended by the loaded arc, where P is the load of failure, R is the radius of the disc, and L is the thickness of the disc. A definition of the splitting tensile strength is suggested. For practical purposes, the suitable length of the loaded arc and an approximation of the splitting tensile strength are suggested. © 1987, The Society of Materials Science, Japan. All rights reserved.