- Steel and composite joints
The details of joints used in steel-framed and composite construction vary widely and depend on a variety of factors, such as the basic design philosophy and assumptions of the framing system. If a “simple” or “gravity” frame is used, then the assumption is that beams are simply supported, with a separate bracing system or structural core resisting horizontal forces on the frame. In this case, the basic role of beam-end joints is to carry the vertical end reactions of the beams. If the frame is designed to carry horizontal loads without a separate bracing system, then the beam-to-column joints are designed as either rigid or semirigid and must carry combinations of moment and vertical force. In either case, the joints adopted will have both moment and vertical force resistance to some extent, but their design details will be different.