Shear design off high strength concrete beams — Canadian code perspective

Abstract

The paper presents the results of an investigation of the influence of concrete compressive strength on the shear strength of reinforced concrete beams, both nonprestressed and prestressed. A total of 132 existing tests on high strength concrete beams, with and without shear reinforcement, were analyzed and compared with the shear design provisions of the CSA Standard CAN3-A23.3-M94 and the previous version of the code, CAN3-A23.3-M84. The main parameter in the investigation was the concrete compressive strength. Owing to the complex nature of shear behaviour and the interdependence of the factors affecting shear strength, other parameters such as the shear span to depth ratio, the longitudinal reinforcement ratio, and the amount of shear reinforcement were varied, as well as the concrete strength. Key words: shear, beams, high strength concrete, code methods, shear reinforcement index, shear ratio, predictions, strength.