Escaleritas Viaduct, Las Palmas de Gran Canaria, Spain

The Escaleritas Viaduct (Las Palmas de Gran Canaria, Spain) is an urban structure that links the districts of Escaleritas and La Feria, and provides this ever-growing area with a great spatial sense. The viaduct has a length of 220 m, divided in four spans of 100 m (the cable-stayed span), 42 m, 42 m and 36 m, respectively. The steel-concrete composite box section of the deck is supported by the piers in a single bearing point, creating a torsion span of 220 m. A 36 m high steel pylon connects the front stays supporting the deck (along its longitudinal axis) with two groups of retention stays, which are anchored to two retention blocks placed behind the abutment 1. The deck bridge was divided into segments; these segments were lifted with cranes and assembled over temporary piers, which were removed after the tensioning of the stays. A three-dimensional (3D) beam model, taking into account the construction process, was considered for the general calculation of the bridge. The most detailed analysis of the deck and the pylon was carried out by means of a shell Finite Element Model (FEM). Finally, the tensioning project is described. The Escaleritas Viaduct project arises from the need to join the districts of Escaleritas and La Feria del Atlántico. The Las Palmas de Gran Canaria City Council and the Gran Canaria Island Council invited tenders to provide the necessary connection to cross the La Ballena gully, a large depression separating the districts that is at present a continually expanding urban park. Among the other infrastructure already present, the main obstacle was the artificial tunnel that intersects the horizontal alignment of the new road at a 51° skew angle. For this reason, the larger viaduct span needed to be just at the start of the bridge. The position of the abutments was almost fixed, because the new road will be the continuation of the existing streets at both sides of the gully. Consequently, the asymmetric cable-stayed solution for the main span began to take shape. This solution allowed a span distribution of 100, 42, 42 and 36 m, optimizing the transverse visibility of the viaduct. Moreover, a single typology having a minimum uniform depth along the whole viaduct resulted in a better economic performance of the deck's cross-section (Fig. 1). The bridge has a constant slope of 1,5% in the vertical alignment, whereas the plan view shows that the main span lies inside a straight horizontal alignment, followed by a leftward circular alignment of 450 m radius (Fig. 2).