Influence of mineral admixtures on the structural behaviour of high performance reinforced concrete beams and columns

Abstract

Mineral admixtures act as pozzolanic materials as well as micro fillers. Their use in High Performance Concrete (HPC) enhances its properties, in strength and in durability. The scope of the present study is to investigate the effect of mineral admixtures namely silica fume, metakaolin and fly ash towards the functioning performance of High Performance Concrete. An experimental study was carried out to study the behaviour of beams made out of high performance concrete, in shear and flexure. The beams were tested under two point loading till their failure. The flexural behaviour was studied with respect to load-deflection and moment-curvature and thereby, the optimum mix proportions were obtained for shear and flexure. In a similar manner, tests were conducted on short and slender columns made out of high performance concrete. Glass Fibre Reinforced Polymers (GFRP) and Isopthalic resin were used for the repair of damaged beam and column specimens. An analytical study was carried out using Artificial Neural Network (ANN) for the prediction of compressive strength, durability and the load carrying capacity of beams and columns cast with HPC. The test results of the neural network models have indicated that neural networks could be adopted for predicting compressive strength, durability factors and also load carrying capacity of members with reasonable accuracy. ANSYS models were developed for shear, flexure beam and for short and slender columns. From the experimental and analytical studies conducted, it is thus concluded that the addition of mineral admixtures have pivotal role in the development of strength and durability aspects of structural members. In total, the structural members cast with HPC have performed much better in comparison to those cast with conventional concrete.