Design and construction of the Route 27 viaduct on the highway from San José to Puerto Caldera, Costa Rica. The structure as a diversion makes it possible to address the landslide zone identified in the geotechnical report by means of a single simply supported span. As the span of the structure measures 145 m, a bowstring arch with a lower deck is considered to be the most appropriate solution as it is lighter and easier to build than the base alternative.
The arch is composed of the arch itself, which is the upper chord, and the longitudinal bracing beam, which is the lower chord.
The cross-section in both cases is metal casing of constant dimensions where only the thickness of the wings and webs varies in order to optimise the structure’s weight. The two previous elements are joined together by means of suspension cables.