road
Bridge over the Vouga River on the EN1
The Vouga River Bridge is located on the EN1, in the municipality of Águeda, district of Aveiro, and was built in 1980. It is a structure with 15 spans with a total length of 556.0 m and a width of 16.0 m. The deck is made of reinforced concrete and longitudinally prestressed, with intermediate spans of 38.0 m and two extreme spans of 29.0 m. The bridge consists of two continuous and equal structures, formed by an extreme span and six intermediate spans, the last extending to the outside of the 7th pillar by means of a cantilever with a span of 8.0 m. Over the two cantilevers, corresponding to the two structures described, a central span is simply supported – the gerber span – which spans the 22.0 m gap between them.
The deck is formed by four prestressed longitudinal beams of variable height and constant thickness and by joists in the thirds of the span and on the supports. The fourteen pillars, in reinforced concrete, are made up of a central shaft with a constant section along the entire height, topped by a capital. The foundations of the pillars are indirect, constituted by a group of piles, or direct, through a footing. The two abutments are in a reinforced concrete vault and have a direct foundation. The connection of the deck to the pillars and abutments is carried out by means of lead joints equipped with bolts.
In view of the information collected, obtained through the main inspection, the analysis of the results obtained regarding the characterization tests of the materials and the structural evaluation, it was possible to indicate the types of rehabilitation work of the work of art.
This work involves repairing visible damage, namely:
Eliminate cracking and delamination and crushing existing in the concrete;
Carry out a painting that prevents the evolution of concrete degradation;
Replace the gerber leg support devices.
To replace the support equipment, it will be necessary to build temporary towers, approximately 15.0 m high, on top of which hydraulic jacks will be installed to lift the gerber section. Given the characteristics of the soil, these towers have an indirect foundation - micropiles. This work will be carried out by gerber half spans, allowing for alternating circulation. Lifting/laying operations will be synchronized with the placement/removal of ballast on the cantilevers in order to avoid significant changes in the state of tension of the deck sections close to the gerber span.