Fatigue properties of reactive powder concrete with different steel fiber ratios

The fatigue properties of RPC (Reactive Powder Concrete) with different steel fiber ratios of 0%, 1.5% and 3% in volume were investigated with the uniaxial compressive fatigue test. The results showed that the splitting failure mode appeared for pure RPC specimens without steel fiber, but the shear failure mode occurred for those specimens with steel fiber of 1.5% or 3% in volume. The fatigue life and strength increased with the increase of steel fiber ratio; the macroscopic damage, ε-n/N_f curves and the evolution of the fatigue deformation modulus of tested RPC experienced three stages. With the increase of steel fiber ratio, the first and third stages of ε-n/N_f curves were lengthened, and the fatigue deformation modulus significantly increased with the increase of the steel fiber ratio corresponding to the same n/N_f. It is suggested that the ratio of fatigue deformation modulus to the initial elastic modulus should be 0.7 and 0.75 for the RPC with a steel fiber ratio of 1.5% and 3%, respectively.