A bridge in the sacred valley of the Incas.

The Maranura Bridge is part of the project “DEFINITIVE STUDY FOR THE CONSTRUCTION OF THE MARANURA BRIDGE AND ITS ACCESSES” of the Peruvian Ministry of Transport and Communications – PROVIAS, which was awarded to the Maranura Consortium, formed by the Spanish firm CPS Ingenieros and Geoconsult.

CFC and HUALCA Ingenieros have carried out the study of alternatives and the construction project of the bridge that is the object of this contract.

The Maranura Bridge over the Vilcanota River is located in the Sacred Valley of the Incas, the Andes, 30 km from the Sanctuary of Machu Pichu, in the Cusco region.

It has a total length of 202 m, 150 m corresponding to the parabolic arch of 15 m of arrow (1/10L) that saves the riverbed at a height of about 100 m.

Given the location of the bridge in a remote area, the solution envisaged was to use light elements of reduced dimensions to facilitate its construction.

For this reason, a light configuration was chosen for the arch by means of a double thread with an octagonal box section lightened internally in order to be able to be executed by folding the half-arches.

The threads are transversely braced every 15 m in the column support sections by means of rectangular beams.

The 11.70 m wide deck was also resolved with a light and simple solution of constructing a cross section in “π” of reinforced concrete with the ribs located on the vertical of the arches on which they are supported by rectangular pillars. The lateral support is carried out on neoprene supports dimensioned to achieve sufficient seismic isolation so as not to penalize the behavior of these and of the arch.

The initial system of construction by folding the semi-arches was modified at the request of the builder for a construction on a metal auxiliary self-supporting arch, since he had recently used this system in another project and the formwork modules could be adapted without too much complication to the geometry of the Maranura arch.