Reliability of indirect tensile strength test on homogenous material using finite element method

Abstract

The difficulties associated with performing a direct tensile test on a rock specimen have led to a number of indirect methods for assessing the tensile strength. This study focuses on the influence of the contact area between loading plates and the sample on the stress distribution, deformations and cracks initiation within homogenous material (Acrylic) disc samples subjected to indirect tensile loading by Brazilian testing with flattened plates. Finite element software of RS2 from Rocscience was utilized to simulate the condition and compared with the laboratory testing to generate gain in depth understanding of the Brazilian test. The analysis showed that the indirect tensile strength dramatically decreased as the contact area increased. Furthermore, from the simulation work, it is observed that cracks initiates as points near to the loading plates rather than centre, this condition occurred due to the induced shear stresses initiate near the flattened loading plates.