Structural behaviour of reinforced-concrete continuous deep beams with web openings

Ten reinforced- concrete continuous deep beams with openings were tested to failure. The main variables investigated were the shear span- to- overall depth ratio, and the size and location of openings. Two failure modes influenced by the size and location of web openings regardless of the shear span- to- overall depth ratio were observed. The normalised load capacity of beams having a web opening area ratio of 0.025 within exterior shear spans was approximately similar to that of their companion solid beams. Continuous deep beams having web openings within interior shear spans exhibited a higher load capacity reduction with the increase of the opening size, similar to simply supported deep beams with web openings. Formulae based on the upper bound analysis of the plasticity theory were proposed to predict the load capacity of continuous deep beams with web openings. Comparisons between the measured and predicted load capacities showed a good agreement.