DURABILITY PROPERTIES OF HIGH STRENGTH CONCRETE INCORPORATING DIFFERENT MINERAL ADMIXTURES

Abstract

The durability of a structural element is of utmost importance for the required serviceability at reasonable costs. Low durability materials are not preferred in construction because of the additional cost incurred later for repair and retrofitting required. The porous nature of concrete, the vulnerability of the steel reinforcement, and the slight compatibility between the two, inevitably lead to the deterioration of the reinforced concrete. Deterioration is influenced by both internal and external factors. Internal factors that should be considered include type of aggregates used, water‐cement ratio, type of reinforcement, and casting method. The durability performance of the developed high strength concrete with incorporation of Ultrafine forms of Silica fume, Slag and Fly ash was inspected for different parameters such as chloride migration coefficient, carbonation depth, surface electrical resistivity, water absorption rate, water permeability, chloride induced corrosion, resistance to acid attack, volume of permeable pore space. In accelerated chloride migration test, the migration coefficient for high strength concrete was obtained at 28 days and 56 days. Ultrafine Silica fume performed better than other pozzolanic incorporations of Ultra fine forms of Slag and Fly ash. To get an idea of rate of corrosion in different concrete, Electrical Resistivity test was performed and the results indicated that the concrete containing Ultrafine Silica fume found with highest electrical resistivity out of the three-concrete mix.