1812 Constitution Bridge (Cádiz)

Project

A set of studies

The design project is managed and developed in the design-project office of Carlos Fernández Casado, S.L. The study, development and construction of the bridge has called for a host of drawings, hundreds of plans, structural reconstructions, etc, both of the bridge in general and the construction details of each component.

Javier Manterola Armisén

Javier Manterola Armisén, project manager, a bridge engineer at Carlos Fernández Casado, S.L.

A set of studies

Objective

Provide a new access route into Cadiz by spanning the navigation channel without interrupting traffic, as occurs on the Carranza Bridge.

Aerial photo of Bay of Cadiz

The 1812 Constitution Bridge affords access to the city of Cadiz from the mainland within the municipal district of Puerto Real. It makes up the third access route into the city together with the San Fernando isthmus and the José León de Carranza Bridge.

It is a high-capacity bridge with two road lanes either way and two railway lines, over which the Metropolitan tram of Cadiz Bay runs.

Map of Bay of Cadiz(Spain)

Four bridges in one

I Access viaduct from Puerto Real

Length 1182 m.

The access section from Puerto Real has a variable slope of up to 5%, a total length of 1182 m and a width varying from 40 to 30.5 m. The whole access section is made of pre-stressed concrete.


It is divided into three subsections:
- The first section has spans of 40 m and 32 m alongside abutment 2, since the pylon height drops substantially upon approaching the ground.
- The second section caters for under-bridge traffic and access to ribbon-development factories.
- The section alongside the cable-stayed bridge, with three 75-m spans.

I Access viaduct from Puerto Real

II Cable-stayed bridge

Length 1180 m.

Its 69-m clearance makes it one of the world’s highest bridges. The only way of achieving such a span with today’s technological knowhow is to build a cable-stayed bridge . From two 180-m towers a total of 176 stay cables fan out to support the 540-m main span and each one of the two 320-m balancing spans.


The lintel is 34.3 m wide. It houses four 3.5-m road lanes, two in each direction, two tram tracks, pavements, guards, stay housings and traffic wind-breaks. The structure of this lintel is light, aerodynamic and slim. This is achieved by using a mixed 3-m thick steel and concrete structure with profiled edges.

II Cable-stayed bridge

III Removable deck section

Length 150 m.

III Removable deck section

To allow passage of ships over 69 m. tall, which is the maximum bridge clearance, a removable deck section has been included in the design.


It is a simply supported 150-m-span bridge with a depth tapering from 8 m in the centre of the span to 3 m at each pier. At each end the lintel is identical to the typical cross section of the whole bridge.

IV Access viaduct to Cadiz North

Length 570 m.

IV Access viaduct to Cadiz North

The access section from the Cadiz side is 570 m long with seven 75-m spans plus one 45-m span next to the city.
The section width is 30.5 m.
The lengthwise slope is 5%.
Its lintel is profiled, slim, aerodynamic, of a mixed steel-concrete structure.


Gobierno de España, Ministerio de Fomento, Dragados, Drace, CFCSL, Real Academia de Bellas Artes de San Fernando