Constantine viaduct: a new landmark for the city of bridges

The core part of the Constantine viaduct is a 756 m long cable-stayed bridge currently under construction in Constantine, Algeria. Due to its slender appearance, clear visual lines and prominent location, it will be another landmark structure for a city already known for its historic and beautiful bridges. This paper focuses on the design and construction of the cable-stayed bridge with its 259 m main span, central pylons, central cable plane and post-tensioned concrete box girder with internal and external tendons. The architectural form is characterised by extensive use of curved structural elements. The design considerations associated with placing an aesthetically pleasing major bridge in the centre of an old city with many restrictions to alignment and consequently complex geometry are addressed. The paper outlines key structural elements and selected details such as the anchorage blocks for the stay cables in the bridge girder and the monolithic connection between the pylon and the deck. It also reports on the construction methodology and control.