Experimental study on large deflections of beam–column joints with reinforced flange plates

Abstract

Web openings facilitate the passage of pipes and enable plastic hinge transfer. However, because these openings reduce the ultimate load at certain values, reinforced flange plates are introduced into the beam–column connections with web openings. In this study, five experimental specimens were constructed and tested, including one base specimen with only web openings, one base specimen with only flange plates, and three specimens with both flange plates and web openings. The failure modes, load–displacement responses, deflection shapes, and deformation capacity were mainly considered. Subsequently, after experimental verification, the thickness and length of the flange plates, as well as the position and diameter of the web openings were studied by numerical simulation. The results indicate that the catenary contribution coefficients and internal energies of the specimens with reinforced flange plates were higher than those of the base specimens. We also concluded that the optimal thickness of the flange plate is equal to that of the beam flange, and the optimal diameter is the maximum web opening that meets the specification requirements. In addition, the mechanical properties gradually increased with an increase the distance a from the web opening to the beam end for a ≤ 190 mm and then decreased for a > 190 mm.