DefinePK

Abstract

This paper focuses with the investigation of the factors affecting the post web buckling of castellated beams with intermediate plate in which the analytical results of thirty castellated beams cases were summarized for this purposes study. This research aims to find the effect of main factors that controlled the buckling behavior of castellated beams. These factors include the cutting angle (45°, 60°, 90°), the increment plate height (0,50,100,150,200) mm, the element formulation (thin and thick shell), and finally the loading conditions (shear force, bending moment). The SAP 2000 software was applied to find the buckling load factor by using four nodes shell element to represent the castellated beam sections web and flange. The obtained results showed that the thick element type formulation gave higher values by range 10% to 15% according to the cutting angle and the ultimate buckling shear and moment forces decrease with increasing the intermediate plate height by a nonlinear amount so that the cutting angle 60 ° gives the higher shear section shear capacity and values 90° gives higher section moment capacity. Also, 12 regression models had been developed between the reduction buckling section capacity and the intermediate plate height ratio. In addition, the effect of the intermediate plate height changes the mode of buckling failure from combined tee-web failure to web portion. Finally, the plate height increases causing shifting down the domain of interaction diagram of shear force and bending moment without changing its shape.