Behaviour of steel fibre reinforced self compacting concrete one way slabs

Abstract

This paper presents the details of investigation on the effect of steel fibre on the flexural behaviour of simply supported one way SCC slabs. A total number of nine specimens were cast and tested with steel fibres of aspect ratio of 50 and volume fraction of 0 %, 0.5% and 0.75%. The load deflection characteristics, first crack load, ultimate load, initiation, propagation and widening of cracks were investigated. Addition of fibres enhanced the first crack load and post cracking behavior. A marginal improvement in the ultimate strength was observed. Ductility and toughness characteristics improved significantly due to the fibre addition. The optimum volume fraction of fibres in terms of strength and ductility was found to be 0.75% percent. Experimental values of ultimate moment were compared with analytical model for simply supported fibre reinforced flexural members and it was noted that the conventional model underestimates the ultimate moment in the case of fibre reinforced SCC flexural members. Hence a modification has been proposed to the existing model to predict ultimate moment of one way steel fibre reinforced self compacting concrete (SFRSCC) slabs.