Shear – moment analysis of reinforced high strength concrete beams containing steel fibres

Abstract

This paper concerns the incorporation of steel fibres in singly reinforced high strength concrete beams without stirrups failing under the combined effect of flexure and shear. A new equation for predicting the shear strength of reinforced high strength concrete beams is developed. This equation shows a good correlation with own test data of 16 reinforced high strength concrete beams with and without steel fibres and numerous published experimental data for beams with concrete compressive strength up to 140 MPa. The flexural capacity of reinforced high strength concrete beams is also investigated. The existing ACI method for predicting the flexural strength of steel fibre concrete composites is slightly modified to be applicable for high strength concrete. Based on the proposed equations, an analytical model is developed for predicting the relative flexural capacity, i.e., the ratio of the moment with shear interaction to the pure flexural moment. Key words: high strength concrete, steel fibre, shear strength, flexural strength, stirrups, web reinforcement.