Influence of Frost Damage on Performance of Engineered Cementitious Composites

Although engineered cementitious composites (ECC) exhibit tensile strain hardening and multiple microcracking characteristics, whether the performance of ECC changes obviously under freezing-thawing conditions is important for the design and maintenance of buildings in the areas with freeze-thaw exposure. Results indicates that, as the number of freeze-thawing cycles increase, the PVA fiber/matrix interfacial bonding strength decreases, more fibers can be pulled out, thereby resulting in an increasing deformation on ECC. The results of water capillary absorption, chloride penetration and carbonation on ECC reveal that the frost damage has little effect on ECC. In addition, the steel bar-normal concrete interfacial ultimate bonding strength decreases linearly with the increase in the number of freeze-thawing cycles, the specimen splits failure. However, for the ECC, the steel bar-ECC interfacial ultimate bonding strength decreases with the increase in the number of freeze-thawing cycles, the pull-out failure occurs.