Analysis of Design Criteria for Shear Strength of High-Performance Reinforced Concrete Beams

This paper presents a comparative analysis of the predicted shear capacities of beams obtained by using several design criteria with respect to test results of reinforced concrete beams built with high-performance concrete (fc > 50 MPa). The database contains a total of 234 test beams with and without web reinforcement. The employed design criteria are EUROCODE 2 and the simplified methods of ACI 318 and Canadian CSA A23.3. The Brazilian code (NBR 6118) procedures and Zsutty’s method are also included in the study. Statistics of the ratio of test-to-predicted shear capacity are used to evaluate the adequacy of these design models in terms of safety, precision, and economy. The effects of the depth of the beams, concrete compressive strength, and the amount of longitudinal and web reinforcement are also investigated. The results show that for the beams without web reinforcement, EUROCODE 2, and Zsutty’s method are the most suitable procedures; NBR 6118 provisions, on the other hand, need adjustments because they can have inadequate margins of safety. The performance of the shear predicting models of ACI 318, the CSA A23.3 and NBR 6118 (θ = 45°) for beams with web reinforcement are similar but significantly biased; EUROCODE 2, in this case, is extremely conservative and consequently not economical. Overall, Zsutty’s method was the best predicting model among those included in this study.