The bi-material circular disc compressed between the jaws of the ISRM standardized apparatus for the Brazilian test

AbstractThe mechanical response of a circular bi-material disc, squeezed between circular jaws, is studied numerically. The disc is composed by two identical (from the geometric point of view) almost semi-circular discs joined together with the aid of a thin layer of a third material. The numerical model is validated against experimental data obtained with the aid of Digital Image Correlation technique. The influence of various (geometric and material) parameters on the stress- and displacement-fields developed all over the composite disc is studied comparatively. Attention is paid to the role of the thickness and stiffness of the intermediate layer as it is quantified by its modulus of elasticity. The influence of the inclination of the interfacial layer (with respect to the axis of the load imposed) is also considered. It is concluded that the role of the interfacial layer is by no means negligible even in case its thickness is very small with respect to the disc radius