Development of Multiscale Fiber-Reinforced Engineered Cementitious Composites with PVA Fiber and CaCO3 Whisker

Engineered cementitious composites (ECCs) have attracted increasing attention in recent years owing to its unique properties of tensile strain hardening behavior and tight multiple cracks. A new kind of multiscale ECC (MS-ECC) that contains polyvinyl alcohol (PVA) fibers and calcium carbonate (CaCO3) whiskers was designed based on the design models of ECC. Nine series of MS-ECC proportions were prepared, and the mechanical properties, including compressive strength, uniaxial tensile behavior, flexural behavior, and microstructures of the mixtures, were studied. The experimental results indicate that the strength of MS-ECCs was enhanced with the proper addition of CaCO3 whiskers. Moreover, the addition of CaCO3 whiskers increased the robustness of the ECC material. The microstructure experiment demonstrated that the CaCO3 whiskers and PVA fibers could effectively interact with different scales.