The prescriptions provided by the codes of practice for the assessment of the minimum rein- forcement amount in reinforced concrete beams usually disregard the nonlinear contribution of concrete in tension and the size-scale effects. In the present paper, these phenomena…
The prescriptions provided by the codes of practice for the assessment of the minimum rein- forcement amount in reinforced concrete beams usually disregard the nonlinear contribution of concrete in tension and the size-scale effects. In the present paper, these phenomena are correctly taken into account in the description of the flexural failure in lightly reinforced concrete beams by means of a numerical algorithm based on Nonlinear Fracture Mechanics. In this context, the application of Dimensional Analysis permits a reduction in the number of the governing parameters. In particular, it is analytically demonstrated that only two nondimensional parameters, N and s, are responsible for the brittle-to-ductile transition in the mechani- P cal response. According to this approach, a new formula suitable for the evaluation of the minimum rein- forcement in practical applications is proposed. A comparison with experimental results demonstrates the ef- fectiveness of the proposed model.