Reinforced concrete deep beams : behaviour, analysis and design

Abstract

The work described in this thesis is concerned with the behaviour, analysis and design of reinforced concrete beams. A brief historical review of the methods of analysis on deep beams is given. The current major codes of practice and design manuals associated with reinforced concrete deep beams are reviewed. This study has been useful in identifying the limitations of the current design documents on the subject of deep beams. Because of the acute shortage of information regarding buckling, web-opening and combined loading, three test programmes are performed to provide experimental evidence on these topics. Their behaviour is examined in terms crack developments, crack patterns, modes of failure, in-plane and lateral displacements, ultimate loads, strains and stresses. The ultimate buckling strength of the slender deep beams without web-openings are analysed using the methods described in the CIRIA Guide (1977]. Adopting the same methods in the guide, an attempt has been made to analyse the buckling strength of deep beams with web-openings. Based on the structural idealization of Kong et al (1973a], a modified approach is proposed for the ultimate shear strength of deep beams with web-openings. In addition, the CIRIA ultimate shear interaction equation for deep beams under combined top and bottom loadings is studied and an equation is proposed for the uniformly distributed loading cases. Finally, based upon these findings, some design recommendations are given.