ABSTRACT
Some of the most important steel-framed buildings fall in the classification of single-storey, one-way-spanning structures. Detailed designs are given for a pinned-base portal using plastic theory and a two-pinned arch using elastic theory. The portal is designed using universal beam sections. Two designs are given for the arch – one using rectangular hollow sections and one lattice construction. The chapter briefly outlines the design of a portal constructed from built-up tapered sections. The design process for the tapered welded I-section member portals commonly used in the USA. The design is made using elastic theory. The portal members are made deeper at the eaves. The columns taper to the base and the rafters may be single or double tapered. The arched roof is most commonly constructed in the form of a circular arc. It has been used extensively for sports arenas, bus and rail terminals, and warehouses.
