Effects of steel fiber reinforcement on surface wear resistance of self-compacting repair mortars

Self-compacting repair mortars (SCRM), as new technology products, are especially preferred for the rehabilitation and repair of reinforced concrete structures. The self-compactability of repair mortars may bring considerable advantages at narrow mould systems. However, due to the high powder content and absence of coarse aggregate, plain SCRMs are susceptible to surface abrasion, especially in case of repair of surfaces under high rates of abrasion (floors, slabs). Steel fiber reinforcement can be an excellent solution for the abrasion resistance problem of SCRMs. However, the optimum amount of fiber reinforcement to sustain self-compactability should be pre-determined. In this study, the optimum superplasticizer dosage and the maximum possible amount of fiber addition, which maintain the self-compactability and stability, was determined for mortars incorporating steel fibers. In addition, the mechanical performance and abrasion resistance of SCRMs prepared by using these fibers were determined. It was concluded that steel fibers can have rheological and mechanical synergistic effects, and that optimised fiber – superplasticizer dosage combinations can better improve the wear resistance while maintaining adequate flow properties for FR-SCRM.