Hydration and internal curing properties of plant-based natural fiber-reinforced cement composites

Abstract

This study investigated the effect of natural fibers on the hydration reaction of cement, in addition to the applicability of such fibers as internal curing materials. More specifically, cement com-posites were prepared by adding abaca, hemp, and jute fibers (0.5 % relative to the cement weight). Subsequently, the hydration heat and ultrasonic pulse velocity were measured over time for each specimen, and the obtained values were used to calculate their setting times. In addition, the degrees of autogenous shrinkage were measured for the natural fiber-reinforced cement composites. It was found that the natural fibers increased the setting time due to their chemical components delaying the hydration reaction of cement. Finally, in the natural fiber-reinforced cement composites, the compressive strength tended to decrease and the long-term strength improvement rate varied depending on the degree of moisture absorption by the natural fibers.