Components of the Fracture Energy in Steel Fiber Reinforced Concrete (SFRC) Elements.

The quantity of energy absorbed during rupture correctly characterizes the quality of fiber reinforced cement-based materials. In this paper the complicated process of crack opening and propagation in SFRC beams is represented in the form of five separate mechanisms described by simple analytical formulas. A series of SFRC beams with initial notches, tested with precise measurements of deflections and crack width development is used to verify these formulas. The fracture energy calculated as a sum of the energies absorbed in the five above-mentioned mechanisms is compared with the work of the external load, obtained from the load-deflection curve. The results obtained are in good agreement for a majority of beams and therefore the proposed formulas may be considered as appropriate for describing the fracture process.