Replacement of 4 stay cables on the Vasco De Gama bridge in Portugal

Last year, it was hit by a truck, causing a fire which damaged four stay cables. Inspections and tests carried out by Freyssinet’s teams concluded that 4 stay cables, the longest in the central span, would have to be replaced due to a decrease in their durability.

Started last April, the project consists of replacing the 4 stay cables one by one, without adding temporary ones.

The main challenges faced:

• There is no interruption of traffic, we work in a neutralized corridor of 6 meters wide without interfering with the users’ lanes.
• Our scaffolding is suspended at the top of the pylon at a height of almost 150 meters. This allows our technicians to access the stay cable from outside the tower.
• Complex checks and continuous monitoring of the tension of the stay cables and the geometry of the structure are being used. It is essential to work on the adjacent stay cables to relieve the bending in the lateral deck beam affected by the removal of a cable.
• In line with our sustainable engagement, we are committed to reusing some of the undamaged material. This is a first and it is also satisfying to note the excellent state of conservation of our ducts, strands and anchorages.

Currently, we are dismantling the fourth and final stay cable.

Bridge concessionaire: Lusoponte
Control: Arcadis and Professor D. Michel Virlogeux

Learn more about our capabilities on Stay cables maintenance