Experimental Research on Equivalent Rectangular Opening Castellated Beam with Fillet Corner

Abstract

Nowadays the use of castellated beam has been admired due to its beneficial functions like a light in weight, easy to erect, economical and stronger. The castellated beam is manufactured from its parent solid I beam by cutting it in a zigzag pattern and again joining it by welding so that the depth of the beam increases. Hence, due to an increase in depth of beam load carrying capacity of the parent I section is increased with the same quantity of material and weight. The increase in depth of the castellated beam leads to web post-buckling and lateral-torsional buckling failure when these beams are subjected to loading. There are many other modes of failure like the formation of flexure mechanism, lateral-torsional buckling, and formation of Vierendeel mechanism, rupture of the welded joint in a web post and shear buckling of a web post which needs to be taken care of. Hence, in the present paper, an attempt has been made to evaluate existing literature, concerned with the strength of the beam by providing a rectangular opening and rectangular opening equivalent to diagonal & hexagonal opening with different angles of opening 300, 450 & 600. The fillet radius is provided to the corner of the rectangular opening as a result of a 54% increase in the load-carrying capacity of the rectangular section compared to the regular rectangular section.