ABSTRACT
Arches, vaults, domes and shells are structures that work in compression to divert gravity loads to the sides in order to create occupiable spaces. The terms most often used in describing the shape of the Gateway Arch are parabola, catenary, and weighted catenary. Commemorative arches designed to be lasting monuments date back thousands of years, with a number still standing from the days of ancient Rome. A catenary is the shape assumed by a hanging chain or a flexible cord of uniform density. A collaborator of Felix Candela's, Colin Faber gave detailed technical descriptions of his concrete shells with calculations of their statics, descriptions of structural details, and plenty of construction photographs— with no hint of concerns for a larger intellectual or political discourse. The primary structure of the dome is provided by a series of glue-laminated timber ribs, each of which carries load by means of a combination of axial compressive force and bending behavior.
