Modelling the Ultimate Shear Behaviour of Deep Beams with Web Openings

Web openings are inevitably installed in deep beams in practice, while most of the research is focused on the shear behaviour of solid deep beams. The existence of web openings can reduce significantly the shear capacity of deep beams and therefore cause safety problems. In this study, the typical shear failure modes and load transfer mechanisms of deep beams with web openings are firstly investigated, and based on the investigation a kinematic model is proposed for the shear capacity prediction. This kinematic model stems from the existing two parameter kinematic theory (2PKT), which was shown to provide satisfying predictions on shear capacity of solid deep beams. In the proposed model, one shear span is divided into two sub shear spans below and above the web opening, respectively. The steel layout at beam end beyond the web opening is crucial for resisting shear transferred above the web opening. Twenty seven deep beam specimens with web openings are used for the validation. The proposed kinematic model provides satisfying results, i.e. Vexp/Vpre: Avg=1.14 and COV=7.8%.