Reconstruction of cantilevered stone staircase at Christchurch, Belfast

In contrast with the level of understanding of flexural behaviour of reinforced concrete members, shear behaviour remains less well understood. This paper presents the findings of a study carried out with the aim of improving understanding of shear behaviour of continuous reinforced concrete beams without shear reinforcement. The findings are significant since most design methods assume that the shear capacity is the sum of the strength of the unreinforced cross-section and the strength of the reinforcement. An extensive study into the effects of concrete strength, shear span/effective depth ratio, and reinforcement content has been carried out. This study incorporated a laboratory testing programme, coupled with the use of a non-linear finite element model. A design approach for the prediction of shear capacity in continuous members is proposed, based on the findings of the current study. The predicted design approach is compared with those of BS 8110 and Eurocode 2. Paul Keown, BEng, PhD, CEng, MICE Doran Consulting, Lisburn Road, Belfast David J. Cleland, BSc, PhD, CEng, FICE, FIStructE Queen’s University, Belfast BT7 1NN Stephen G. Gilbert, BSc, PhD, CEng, MICE, MIStructE Queen’s University, Belfast BT7 1NN David Sloan, BSc, CEng, MICE Queen’s University, Belfast BT7 1NN