Site, Type, Drawing: Three Keys to Creative Bridge Design

Abstract

The article proposes three essential elements in the bridge design process: site, type and drawing. The site defines the problem. The type relates to structural history. The study of alternatives constantly turns to the open catalogue of types for support. Drawing is the conceptual synthesis that builds on the two previous elements. Bridge design entails drawing as much as analysis and sometimes it is even more about geometry than about engineering. To design is to draw. A discussion of the proposed key design components is followed by a description of several bridges and footbridges designed by the authors: a competition proposal in the United Kingdom, two competition-winning footbridges—over the Drava river in Maribor, Slovenia, and over the Miño river between Spain and Portugal—and two urban bridges built in Riyadh. The presentation of the projects is structured according to the three essential elements proposed (site, type and drawing) and highlights the main characteristics of each project and the key aspects of their design processes. In conclusion, the article proposes several actions to be considered as open instructions or recommendations for bridge design with the aim of being both a design method and a manifesto to encourage creative structural engineering.