Shear behaviour and strength design of cellular beams with circular or elongated openings

摘要

In order to facilitate accurate and practical design of cellular beams with circular or elongated openings in shear against Vierendeel action (VM) and web-post buckling (WPB), this investigation proposes rational design equations based on Direct Strength Method (DSM). Nine steel beams including one solid-web beam and eight cellular beams with different opening's position, opening width, opening size and different openings' number are tested to study the failure mode and shear strength of cellular beams. A three-dimensional nonlinear finite element model is developed for further investigating the shear behaviour of cellular beams. The finite element model is validated by comparing its results with the experimental results. A series of parametric studies, in which various geometric parameters of cellular beams are considered, are performed by using the developed finite element model. Based on numerical results obtained in the parametric study and the experimental results, an accurate model on the basis of the DSM is proposed for predicting the shear strength of cellular beams. The yield shear load, shear loads of VM and WPB and their coupled effects are taken into account in the model. The model is applicable to the cellular beams with circular or elongated opening, and can be used for predicting the shear strength of cellular beams with not only one opening but also multiple openings in a shear span. This model covers a wide range of cellular beams with different opening widths. The theoretical results predicted by the proposed model show good agreement with extensive numerical and experimental results.