Properties of High-Strength Fly Ash Concrete

摘要

An approximately 90 million tonne of fly ash is produced in India yearly. Most of the fly ash produced, is of Class F type. Its percentage utilization is between 13 and 18%. To increase the percentage utilization of Class F fly ash, an investigation was carried out to use it in producing high-strength fly ash concrete. This paper presents results of an experimental investigation carried out to study the properties of high-strength concrete containing 40% Class F fly ash as partial replacement of cement. Tests were performed for fresh concrete properties, compressive strength, compressive stress-strain characteristics, splitting tensile strength, and flexural strength of concrete. Tests for strength properties were performed at the ages of 7, 28, 91 and 365 days. Test results indicated that concrete containing 40% Class F fly ash as partial replacement of cement achieved compressive strength of more than 50 MPa at the age of 28 days, and further increased at the ages of 91 and 365 days. Splitting tensile and flexural strengths were also found to increase with age. Fly ash is an ideal constituent for producing high-strength concrete fly ash concrete as it has inherent ability to contribute to continued strength development through pozzolanic reaction and also to enhanced durability and chemical resistance.