Wide-shallow beams with and without steel fibres: A peculiar behaviour in shear and flexure

This paper reports an experimental campaign on Reinforced Concrete (RC) Wide-Shallow Beams (WSBs) with or without fibres, tested under shear and flexure. A wide-shallow beam is a rather frequent structure in residential buildings in Southern Europe (as in Italy and in Spain). In order to study both the shear and flexural behaviour of WSBs and evaluate the possibility of substituting the minimum conventional transverse reinforcement required by Eurocode 2 with steel fibres, full-scale beams have been tested. Specimens, all 250 mm deep, had two different widths, fibre contents and also, minimum amount of classical shear reinforcement. Results evidenced that a relatively low volume fraction of fibres can significantly increase shear bearing capacity and beam ductility. Moreover, WSBs did not show the typical brittle failure in shear, even without any shear reinforcement, as the effect of fibres was more prominent than in deep beams. Peculiarities of WSBs were evidenced in terms of enhancements both in shear and in flexure. Experimental results have been evaluated in terms of strength, ductility, post-cracking stiffness, shear and flexural cracking, collapse mechanism and fibre effect.