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.

Keywords:

• bridge design
• concept design
• design methodology
• alternative study
• structure and form
• creative design

Acknowledgements

The authors want to acknowledge the Royal Institute of British Architects (RIBA), the Municipality of Maribor (MOM), the Association of Architects of Maribor (Drustvom Arhitektov Maribor (DAM)), the Provincial Council of Pontevedra, the Interreg VA Spain–Portugal—El programa Interreg VA España–Portugal (POCTEP)—programme and the Royal Commission for Riyadh City (RCRC) for their promotion and support of these projects.

Many thanks to Burgos & Garrido Architects for fruitful collaboration in bridge and footbridge projects and competitions over time and particularly for collaborative work in the design of the footbridges over the Drava river in Maribor and over the Miño river.

Acknowledgement and thanks to Javier Gómez Mateo, from Bernabeu Ingenieros, for his work and proposals in the design and development of the Goián–Vila Nova footbridge over the Miño river and to Pierluigi D’Acunto and Patrick Ole Ohlbrock, from ETH Zurich, for their collaboration and support in the form-finding process.

The support provided by the entire IDOM team involved in the projects at company offices in Madrid, Riyadh, Bilbao and Barcelona, and especially structural engineers Manuel Casado, Alfonso Celada, Javier Gómez Guerra, Pere Alfaras and Romina González, as well as worksite manager Ignacio Díaz Morcillo, is gratefully acknowledged.