A Set of Dainty Tied-Arch Bridges: The Formal Expression of the Structural Logic

Abstract

Arch bridges are part of the cultural heritage of all cultures of humanity. However, the tied-arch bridges are a relatively recent creation and their structural behaviour is not obvious for those who do not know the basic principles of structural engineering. However, despite this difficulty in interpreting the flow of forces, the tied-arches also have a strong symbolic significance for the Public. This visual or symbolic force, together with its inherent resistant advantages, such as the slenderness of the deck or their independence from the foundation conditions, make the tied-arches a very suitable solution when it comes to building a bridge in an urban context. In the present paper, several small-scale bow-string arches are presented, all of them built in urban or peri-urban areas. These bridges are characterized by the rational use of resources and by a formalization of the structural elements that make them modest examples of how structural engineering can serve, not only to fulfil a purely functional and resistant purpose, but also to contribute to ennobling the area in which a bridge is built. The examples presented here are: the Najera bridges in La Rioja, the bridge over the Genil river in Granada, the bridge over the Guadalquivir river in Montoro (Córdoba) and the Roquetas Bridge all built in Spain.