Effect of layer orientation on behaviour of 3D-printed rock specimens in indirect tensile testing

Abstract The mineralogical composition, texture and fracture of natural rocks can be complicated due to the inherent heterogeneity of geomechanical properties, making it challenging to understand their behaviour. Due to the intrinsic layer by layer manufacturing process, 3D printing technology enables to create rock-like materials and specimens with known and controllable inhomogeneity. In this study, disc specimens of a rock-like material are fabricated using 3D printing of cement mortar for testing to understand fabric orientation effect on fracture behaviour better. For the first time, a novel technique, named AUSBIT (Adelaide University Snap-back Indirect Tensile test), for Brazilian disc tests is applied for obtaining both strength and snap-back post-peak behaviour of the 3D printed rock-like materials. Adopting Digital Image Correlation (DIC) technique, in conjunction with the use of AUSBIT, allows obtaining full-field strains and their evolutions, showing strong effects of fabric orientation on strain distributions and both pre-and post-peak responses.