Fiber reinforced sulphoaluminate cementitious composites: Mechanical properties and comprehensive evaluation method

The rapid repair of concrete structures is an important research subject, which has attracted the attention of engineers at home and abroad. Here, an early-strength and strain, fast-setting and fast-hardening cementitious composite named as fiber reinforced sulphoaluminate cementitious composites (FRSACC)was developed. The mechanical properties of FRSACC were investigated through a series of experiments, including compressive strength, flexural strength, uniaxial tensile performance, four-point bending performance, three-point bending fracture, and microstructure analysis. The results indicated that these properties were influenced by the curing age, water to binder (W/B) ratio, sand to binder (S/B) ratio, and fly ash (FA) dosage. To be specific, the W/B ratio plays a vital role in achieving desirable mechanical properties at early curing stage, followed by the FA dosage and the S/B ratio. In addition, a facile six-dimensional representation was proposed to assess the overall performance of FRSACC. This comprehensive evaluation method can also be used for other cementitious composites to evaluate and select the better mixture ratio based on mechanical properties, bending toughness and fracture toughness.