Fatigue fracture of fibre reinforced concrete in flexure

• Published in: Materials and structures Vol. 53; no. 3
• Main Authors: Stephen, Stefie J., Gettu, Ravindra
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Netherlands 01.06.2020; Springer Nature B.V
• Subjects: Building construction; Building Materials; Civil Engineering; Crack propagation; Cyclic loads; Engineering; Fatigue failure; Fatigue life; Fiber reinforced concretes; Flexing; Fracture mechanics; Machines; Manufacturing; Materials Science; Metal fatigue; Original Article; Processes; Reinforced concrete; Reinforcing steels; Solid Mechanics; Steel fibers; Stiffness; Theoretical and Applied Mechanics; curves; Critical crack opening; –; Notched beam testing; Fibre reinforced concrete; Fatigue fracture; Fatigue damage; Stiffness degradation
• ISSN: 1359-5997; 1871-6873
• DOI: 10.1617/s11527-020-01488-7

An experimental study on the behaviour of fibre reinforced concrete under flexure is presented, where pre-cracked notched beams were tested under cyclic loading for concrete with different dosages of hooked-ended steel fibres. The fatigue crack growth and stiffness degradation during the cycles are discussed in term of the rate of evolution of crack opening, and the critical crack opening is identified, beyond which the crack growth becomes unstable. S – N curves have been proposed with respect to the critical crack opening as these would be more relevant to design avoiding sudden failure. It is evident that higher dosages of fibres improve the fatigue life of cracked concrete only when the magnitudes of the cyclic loading are high, and that the effect of dosage is insignificant at lower magnitudes. For the fibre concretes considered here, the endurance limit seems to be about 50% of the pre-crack load in the post-peak regime.