Shrinkage reduction of high strength fiber reinforced cementitious composites (HSFRCC) with various water-to-binder ratios

In some applications of high strength fiber reinforced cementitious composites (HSFRCC), shrinkage is an important concern. From the literature, shrinkage can be reduced by the addition of shrinkage reducing admixture (SRA) or replacing Portland cement with sulfoaluminate cement (SAC). This investigation studies the effectiveness of SAC and SRA in reducing the shrinkage of HSFRCC. HSFRCC of water-to-binder ratios 0.19, 0.3 and 0.4 when Portland cement is employed, as well as 0.21, 0.3 and 0.4 with SAC, are tested under both sealed condition (to study autogeneous shrinkage) and drying condition. According to the test results, SAC is more effective in reducing shrinkage of HSFRCC with higher water-to-binder ratio whereas SRA is more effective for HSFRCC with lower water-to-binder ratio. Combined use of SAC and SRA can lead to very significant shrinkage reduction.