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The Alamillo Bridge is a structure in Seville, Andalucia (Spain), which spans the Canal de Alfonso XIII, allowing access to La Cartuja, an island between the canal and the Guadalquivir River. The bridge was constructed as part of infrastructure improvements for Expo 92, which was held on a large site on the island. Construction of the bridge began in 1989 and was completed in 1992 from a design by Santiago Calatrava.

The bridge is of the cantilever spar cable-stayed bridge type and consists of a single pylon, counterbalancing a 200 m span with thirteen lengths of cables. The original intent was to build two symmetrical bridges on either side of the island, but in the end, the Alamillo's singular design has proved most striking.

Qualifications as Structural Art:

The Alamillo Bridge was built more as a monument rather than a piece of structural art. While the leaning mast is very suggestive that the bridge is solely supported by the cables, there is controversy that the deck is may be mostly self supporting since the tension in the cables seems lower than would be expected. To be a good example of structural art, the bridge must also be successful at structural engineering design. The Alamillo Bridge however lacks the principles of efficiency and economy and therefore difficult to classify as structural art.

With no economic constraints on construction, the goal was to create a bridge of symbolic importance. This bridge represents the soaring aspirations of the city of Seville in preparation for Expo'92, and is visible from the top of La Giralda, the sentimental roof of the city, linking Seville's past and present. Similar to to the Brooklyn Bridge, there is an elevated walkway for pedestrians. In addition to the elevated walkway, the Alamillo Bridge features a lookout at the top of the mast, accessible by an enclosed stairway.

Socially, the bridge was expensive but it provided easy access to La Cartuja for high traffic demands during the Expo ’92, utilizing a total of six traffic lanes and a pedestrian walkway. The Alamillo Bridge is one of the great structures still standing and in use long after the Expo ’92.

The Puente del Alamillo is the only bridge that is balanced solely through added weights not requiring and type of back anchorage. There are 54 steel piles under the bridge but they act passively under the mast. The bridge mostly relies on the mass of the mast to counterbalance the roadway through the use of 26 steel cables. The roadway deck incorporates a hexagonal structure that may help support the loads but the structure is hidden in the design.

Calatrava's Sundial Bridge at Turtle Bay located in Redding, California (2004), and Chords Bridge in Jerusalem, Israel, are similar in design to the Alamillo Bridge.