EMPIRICAL RELATIONSHIP BETWEEN MECHANICAL PROPERTIES OF HIGH VOLUME FLY ASH ENGINEERED CEMENTITIOUS COMPOSITES

This study is aimed to investigate compressive strength, flexural strength and shear strength of engineered cementitious composites (ECC) with high volume fly ash by replacing cement with Class F fly ash in the range of 40%, 60%, 80%, and 100% respectively. The experimental results shows that compressive strength and flexural strength decreased at 28 days as the percentage of high volume fly ash increased, but when the curing was increased to 90 days, 40% and 60% high volume fly ash engineered cementitious composite exhibited lesser but similar compressive and flexural strength compared to ECC without fly ash. The shear strength decreased as the percentage of high volume fly ash increased in ECC at 28 days. However, the rate of reduction of shear strength decreased when the curing was increased to 90 days. Based on the experimental results, an empirical relationship (exponential) is proposed between shear strength, compressive strength and flexural strength to predict shear strength from compressive and flexural strength at 28 and 90 days respectively. The percentage difference between the experimental and predicted shear strength from the empirical relationship was observed to be lesser than 14% for both 28 and 90 days, thus exhibiting the degree of accuracy for the proposed relationship.