The reinforcement intervention was based on the seismic isolation of the structure through the introduction of supports with low horizontal stiffness.

The structure develops on a curve with a radius of 588 m, has a length of 206 m between extreme supports, distributed over 7 spans, and a total deck width of 25 m. Between the abutments, the deck rests on transverse portals composed of H-shaped reinforced concrete pillars and a prestressed reinforced concrete box girder.

The intervention

The reinforcement intervention was based on the seismic isolation of the structure through the introduction of supports with low horizontal stiffness.

The pillars were monolithically connected to the transverse portals, so the most critical work consisted of cutting the tops of the pillars with a diamond wire saw, as well as the installation of a system of temporary supports to allow the placement of the new bearings.

Applied Technique

The reinforcement intervention was carried out by introducing elastomeric bearings with a lead core (LRB – Lead Rubber Bearings) and high damping rubber bearings (HDRB – High Damping Rubber Bearings), between the tops of the pillars and the box girder and between the tops of the deck girders and the abutments.

Additional information

It is noteworthy that all structural work was carried out without any interruption of traffic on the 2nd Circular Road, one of Portugal’s busiest roads.