Saint Louis weighted catenary. Universal law and individual genius in the evolution of post-war Modernism

Abstract

When designing the Jefferson Memorial, Eero Saarinen reversed Hooke’s technique to determine the ideal shape of an arc. If the latter laid a flexible line in order to obtain the shape that best fit its weight distribution, the former defined first its layout, and sought later the load’s law for which the chosen profile was optimal. Thus, the Gateway Arch does not follow any of the canonical mathematical functions associated with the study of funicular curves, but something called “weighted catenary”. Its impure character granted it criticism from both supporters of ideal forms and those who favored a freer approach to the design process. However, its ability to assimilate the principles of mechanics in a flexible way, without losing the formal control of the result, was a constant for postwar modernism, eager to enhance its stylistic repertoire without abandoning rationality; it represents the search for balance between submission to natural or cultural laws, and creative freedom for the author. And failing to be canonical for architectural critics, it certainly became iconic for the general public, the true hallmark of postwar American society.