Performance and Design of Composite Beams with Web Openings

摘要

Fifteen tests to failure were carried out on full scale composite beams with web openings. All beams had ribbed slabs using formed steel deck. Ribs were perpendicular to or parallel to the steel section. The effects of moment-shear ratio, partial composite construction, deck rib orientation, slab thickness, opening shape, opening eccentricity, and modification of the deck over the opening are studied. A strength model and three versions of a practical design technique are developed. The peak loads attained by composite beams with ribbed slabs at web openings are governed by the failure of the slab. Rib failure occurs in slabs with transverse ribs, while longitudinal shear failure occurs in slabs with longitudinal ribs. First yield in the steel around the opening does not give an accurate indication of the section capacity. The strength model and the design techniques accurately predict the strength of composite beams at web openings for beams with solid or ribbed slabs.