Investigation the effect of cyclic loading on fracture propagation in rocks by using Computed Tomography (CT) techniques

In Brazilian test, applied diametrical compression stress induces indirect tensile stresses normal to the vertical plane crossing through the rock disc and the ultimate failure occurs at the place where the maximum tensile stress is concentrated. The mechanical behaviour of rock with pre-existing cracks under static loading has been studied widely. In this study, the fracturing behaviour of Brisbane Tuff, under static and cyclic loading has been analysed applying an ISRM standard Cracked Chevron Notched Brazilian Disc (CCNBD) geometry. Specifically, X-ray Computed Tomography (CT) techniques have been used to investigate the fracturing behaviour of rocks under static and cyclic loading. The fracturing behaviour of rocks technically depends on the nature of loading, strength of mineral and text of rocks. Laboratory observations demonstrated that there is a distinct difference in fracturing between the static and cyclic loading. It was found that the cyclic loading had an important effect on micro-fracture propagation through the Fracture Propagation Zone (FPZ)