Effects of Web Openings on the Effective Slab Widths in Composite Steel Beams

Abstract—This paper deals with the behavior of composite beams with particular focus on the effects of web openings on the effective slab width, which is required for simplified structural analysis and design. Current design codes propose values for the effective width which are mostly a function of the beam span ignoring in this way the influence of other important parameters. In addition, effect of web opening is not established in the literature. Several 3D numerical simulations are conducted in this paper in order to illustrate these parameters and accordingly a new methodology is suggested for evaluating the effective width of the composite beams with web openings. The proposed approach is easier to apply in comparison with other existing methods based on stress integration, and provides effective width values which result in a more reliable representation of the actual beam state when simplified analysis is carried out. The application of the proposed revised method indicates that the effective width is influenced by the web opening, and this influence relates to the type of opening and the size of opening and, in many cases, the values obtained can significantly differ from those proposed design codes.