Exploration of Structural Performance of Stiffened Steel-Concrete Composite Beams with Perforated Stiffening Rib Plates

摘要

A ribbed steel plate-concrete composite section (PSRP) was proposed to prevent or limit flexuralrncracking in the negative moment region normally with a spiky rise and rapid reversal. Thernproposed section was composed of concrete and steel plate with perforated stiffening rib plate tornreduce the dependency of shear transfer on interfacial bond. The objective of this study was tornobtain experimental and analytical data essential to investigate, and establish, a design method forrnthe steel plate reinforced concrete against flexural cracking under the service load condition. Thisrnpaper presents the results of a total of eight scale specimens prepared for the comparison test. Sixrnspecimens were reinforced using steel plate with perforated stiffening rib plates, one specimen wasrnreinforced using conventional reinforcing bars and one specimen was reinforced usingrnepoxy-bonded steel plate for comparison. All beam specimens were tested to failure. The testrnresults indicated the steel plate with rib stiffeners can offer a pronounced improvement to therncracking resistance of the concrete. The cracking load for the PSRP specimen with stiffening ribrnplate is three times higher than the specimen reinforced with conventional steel, and two and halfrntimes higher than specimen reinforced with epoxy-bonded steel plate. The perforated stiffening ribrnplate appears to have not only increased interfacial bond area and but also provide a volumetricrnrestraint and confinement to adjoining concrete that improves its material uniformity, in comparisonrnto the discrete and localized line bonding provided by the reinforcing bars. This improvement of thernmaterial uniformity may have led to a significant rise of tensile stress limit of the confined concrete.