Engineered cementitious composites with high-volume fly ash

Engineered, cementitious composites (ECCs) are a breed of high-performance fiber-reinforced cementitious composites (HPFRCC) with significant strain-hardening behavior under tension. As ECCs impart ductility and durability to the structure, the high cement usage in the mixture causes environmental and economical impacts. In this paper, the mechanical performance of ECCs incorporating high volume fly ash and bottom ash is reported. Emphasis is placed on the influence of fly ash content on the key micromechanics properties relevant to composite ductility. It is revealed that a high volume faction of fly ash tends to reduce the polyvinyl alcohol (PVA)fiber/matrix interface bond and matrix toughness in favor of attaining high tensile strain capacity. The limit of cement substitution with ash is constrained by compressive strength development.