An experimental study of steel-concrete composite connections equipped with fuse angles

This paper presents an experimental study of replaceable fuse beam-to-column connections for the steel-concrete composite beams. Two types of composite connections equipped with varied fuse elements were examined. The prediction model for the connection resistance of the proposed composite connection was explored, and the proposition was further examined by a test programme employing three full-scale specimens. The results showed that the inelastic deformation was mainly concentrated in bottom fuse angles, and the remaining steel members were elastic or moderately stressed. The inclusion of the concrete slab would increase the resistance and stiffness of the connection significantly, but the ductility of the connection was compromised. The presence of the concrete slab also affected the neutral axis, and the configuration of the asymmetric fuse arrangement with heavier top layer reinforcement shifted the neutral axis upwards more effectively, further minimising the damage to the concrete slab. The repairability of the composite connection was confirmed by conducting the retest of a specimen with replaced fuse angles. The retest specimen showed a strength reduction due to bolt slippage at the bottom flange. The theoretical model could reasonably predict the yield strength of the fuse connection, but the ultimate strength of the fuse connection was overestimated.