“Centura Bridge” has a 35+85+85+35 span distribution, with a 47 m high central pylon (37 m over the deck) and two intermediate piers.
The need of these piers comes from the impossibility of a higher pylon execution because of the clearance of an airport nearby. Thus, the disposition of those intermediate piers limits the maximum inclination in the cables for ensuring their effectiveness.
The deck, 20.30 m wide, is made up by two steel caissons 2500 mm wide at the bottom, with top flanges of 500 m, so the total width of the longitudinal beam is 3000 mm. Both caissons are joined together by cross girders conserved pin-connected to the longitudinal girders described. Upon the grid conformed by longitudinal and transversal girders profiled steel sheeting 2mm tick is placed, as scaffolding for the pouring of 250 mm of concrete.
Cables are composed by from 78 to 133 parallel wires 7 mm of diameter and are joined to pylon and deck by special pieces of steel welded plates.
The elevations are curve-shaped. In the case of the pylon, such a curvature tries to keep the aspect of the original project and at the same time includes the pylon leg in the cables plane. This pylon is hollow up from the deck. The curvature in abutments and piers comes from the need to adapt their shape to the railway clearance. At the abutments basic functions are separated, the concrete wall withstands the loads coming from the deck, and a reinforced soil wall hold the ground under the road.
It is of highlighting the link between deck and elevations, with lead rubber bearings in the pylon and abutments and free spherical pot bearings in the piers. As the sismic action is very high in the zone with horizontal basis acceleration of the ground of 0.24g, these LRB are specially indicated to dissipate energy by means of a hysteretic cycle.