Evaluation of fibre-reinforced concrete fracture energy through tests on notched round determinate panels with different diameters

The Round Determinate Panel (RDP) test has proven to be a reliable method for designing the fibre dosage of shotcrete used in rockbolting operations of underground mining sites. It remains, however, a method that measures the structural performance of the panel but that does not give any intrinsic property of the material itself. Furthermore, this experimental procedure requires the use of large, heavy panels that could generate safety risks. The feasibility of smaller panel sizes is investigated in this study, as well as the potential for deriving a procedure that would estimate the specific fracture energy of the material. It is based on simple kinematic assumptions and its reliability has been verified by using more complex numerical tools. This research could lead to the revision of the methods currently used to design sprayed fibre-reinforced concrete for tunnel linings.