Effects of different mineral additives on high strength self-compacting mortar properties

Self-compacting cementitious systems are composite materials with high segregation resistance and high deformation properties. In this study, industrial and agricultural wastes such as slag and rice husk ash (RHA) were used as cement replacement materials at a high rate in order to reduce the environmental effects caused by Portland cement. By using 0%, 20%, 40%, slag, and 0%, 15%, and 30% of RHA, prismatic high-strength self-compacting mortar samples of 40x40x160 mm were produced, and 2% polyvinyl alcohol (PVA) fiber was used in the mixtures. The 3, 7, 28 and 90-day compressive and flexural strengths of the laboratory and steam cured samples were tested, and the water absorption, ultrasound transmission rate, and BHA values of the 90-day samples were determined. Slag, RHA, and slag-RHA substitution had a negative effect on the early age strength, but steam curing created significant strength increases in the mechanical strength of the 28-day samples. In both curing conditions, 40% slag-30% RHA substitution resulted in a significant increase in 90-day mechanical strengths. It has been observed that 2% PVA fiber additive affects the strengths positively. KEYWORDS: Self-compacting concrete, Ground granulated blast furnace slag, Rice husk ash, PVA fiber, Mechanical properties