Reinforced concrete deep beams some test results

Abstract

Synopsis thirteen simply supported reinforced concrete deep beams with span/depth ratios of 1,2 and 3 are loaded to failure. The percentage of main reinforcement varies from 0·22 to 1·16 and three modes of failure are reported, namely flexure, diagonal splitting and local crushing. Detailed experimental evidence including some strain measurements is presented to enable the development of the failure mechanism to be monitored. The failure loads are compared with values predicted by CIRIA Guide 2, which is shown to be safe provided that failure is by diagonal splitting (the commonest case in practice). It is argued that a need exists for design recommendations for deep beams with larger span/depth ratios than those covered by the Guide.