Numerical and experimental studies on the effect of loading angle on the validity of flattened Brazilian disc test

Abstract

In this study, effect of loading angle on location of crack initiation in flattened Brazilian disc (FBD) specimens was studied by both numerical and experimental methods. FBD tests were conducted on disc samples with various loading angles and tests were simulated by finite element method (FEM). The results showed that probability of crack initiation at flattened ends of samples where jaws and sample are connected should be considered along with central crack initiation which is a usual prerequisite to have a valid FBD test. In addition, experimental analysis was performed on FBD samples which is rarely observed in literature. Moreover, the loading angle of 30° was determined as an appropriate angle for FBD test that guarantees the occurrence of central crack and avoids crack initiation at flattened ends of samples.