Evaluation of Strength Properties of the Concrete Prepared from Class F Fly Ash

Abstract

Cement is a hazardous and expensive material that is used in the production of concrete, where the cost of the concrete is minimized by replacing the cement with similar cementitious materials. According to the report of the national thermal power corporation, the production of fly ash is rising each year as a result of increasing demand for electricity. In this research paper, an attempt has been done by replacing cement with fly ash as an alternative material. The concrete samples are prepared with different compositions by using different percentages (0%, 10%, 20%, 30%, 40%, 50%, and 60%) of fly ash. In this research, the behaviour of the fly ash concrete is investigated by different strength-related properties; compressive strength, splitting tensile strength, and flexural strength at various curing time periods of 7, 28, 56, 90, and 180 days. In the experimental section, the developed fly ash concrete obtained maximum compressive strength of 83.50N / mm 2, a flexural strength of 6.60N / mm 2 and a splitting tensile strength of 4.90N / mm 2 on the 180th day in the composition of 450kg/m 3 and 0.4W/B ratio. Percentage gain of compressive, split tensile and flexural tests for 450 kg/m3 at 0.4 W/B ratio at 180 days curing is 13%, 9% and 13% with 30% fly ash replacement when compared to 350 kg/m3 binder content. Proportional increase of cement content also leads to increase fly ash content in concrete. Fly ash has potential of filling pores because of having finer particles and performs pozzolanic action which resulted in attaining high strength even after optimum replacement when compared to conventional concrete.