Introduction

In the world of engineering, there has always been a great attraction for the curved shaped of the arch and its resistant qualities. The apparent simplicity and purity of line that forms its shape encloses a structure that is well suited to resisting loads and overcoming excessive light.

Gaius Julius Lacer, the Roman engineer who designed the Alcantara Bridge in 106, concisely defined the resistant mechanism of these structures: Ars ubi material vincitur ipsa sua (in an arch, material triumphs over itself).

Eduardo Torroja, in 1996, showing his admiration for this simple structure, declared: “if the column is pure architecture, the arch is engineering; or rather, if the column is art, the arch is technique; which neither means that the column lacks technique, nor that the arch is incapable of vivid aesthetic expression”.