Properties of mortars with fly ash as fine aggregate

Coal power plants produce million tons waste fly ash worldwide that cause environmental problem and threaten people health. Moreover, its depoting costs are high and need extensively large depot areas. Recycling is a strategy to consume waste content left from several industries. Although fly ash has been used in cement and concrete technology. In concrete technology it has been used as supplementary cementitious material or replacement material with a portion of cement until now. But, it has not been considered as fine aggregate. In this study, the effect of fly ash as fine aggregate in mortars is investigated. Flow ability, unit weight, ultrasound pulse velocity, compressive and flexural strengths, modulus of elasticity, stress-strain behavior and free drying and restrained shrinkage tests were conducted on mortars produced. It was observed that the usage of fly ash as fine aggregate presents a new approach to consume high amount of fly ash without causing significant changes on properties of mortars when it was used at the ratio of 60-70%.