Shear resistance analytical evaluation for RC beams with transverse reinforcement with two different inclinations

An analysis-oriented mechanical model for shear strength evaluation of Reinforced Concrete (RC) beams with transverse reinforcement with two different inclinations, which required a numerical analysis, is turned into a design-oriented analytical model that can easily be utilized for practical purposes. The model assessed the shear resistance, according to the "lower-bound solution", employing a numerical procedure that maximizes the element shear strength varying the stresses in the two sets of transverse reinforcement and the magnitude and inclination of the web concrete compressive stress field. The model is formulated with the aim of representing an extension of Eurocode 2 framework to RC beams with two orders of stirrups. In this paper, an analytical procedure is derived, substituting the former numerical maximization procedure, in order to obtain the optimal values of the aforementioned parameters, for any layout and amount of shear reinforcement. Comparison between shear strength predictions provided by the model and test results available in the literature confirms the model's efficiency.