This study evaluates the effect of sulphoaluminate cement content on the performance of high ductility cementitious composite (HDCC) as repair material. To prepare the HDCC, Portland cement was partially replaced with 10%, 15%, or 20% rapid hardening sulphoaluminate cement. The compressive and flexural strength developments and tensile properties of the sulphoaluminate cement containing HDCC were investigated. The microscopic mechanism by which sulphoaluminate cement affects the macroscopic performance of HDCC was examined by scanning electron microscopy. Before 14 d, the mechanical properties were directly proportional to the sulphoaluminate cement content, but at 28 d, the sulphoaluminate cement content exerted no obvious effect. The sulphoaluminate cement content largely influenced the ultimate tensile strain but little affected the tensile strength. The mechanical properties were optimized in HDCC containing 10% and 15% sulphoaluminate cement. The reduced tensile ductility in sulphoaluminate cement containing HDCC is attributed to the large amount of ettringite formed on the surfaces of the reinforcing PVA (polyvinyl alcohol) fibers.
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