Constitutive Behaviour of Flyash Concretes with Steel Fibres in Ordinary Grades

摘要

Construction activity is increasing all over the world today. To fninimise the construction cost and to increase the performance of structural concrete without losing its original properties is a big challenge before the construction industry. To some extent this can he achieved using pozolanas and fibres in concrete production. The present paper discusses the stress-strain behaviour of such flyash concrete with steel fibres in ordinary grade. M30 grade of concrete was designed using the IS mix design code 10262-1982. Cylinders were east with conventional concrete and flyash with random steel fibres. The cement was replaced by flyash up to 40% at regular intervals of 10%. The split tensile strength of conventional concrete with 1% steel fibres and steel firres flyash concrete were evaluated. Concrete with flyash and steel showed an improvement in ductile behaviour. This paper presents a complete stress-strain behaviour of such concretes. An empirical equation has been proposed to predict the behaviour of such concrete under compression. The static moduli of elasticity of concrete at various percentage replacements of flyash are reported. The energy absorption capacity of steel fibred flyash concretes was evaluated. The percentage of steel fibres added is kept constant at 1% and aspect ratio as 75 for all replacements of flyash. The normalised stress-strain curves were plotted and are reported. The proposed equation showed a good correlation with experimental values.