Between 2005 and 2007, Perta participated in the construction of the Lezíria Bridge through the supply and turnkey assembly of an Olmet U-beam plant.

In this period, 1032 beams were produced, at an average of 4 beams/day, with a zero reject rate.

The U beams, with a height of 1.75 meters and a lower flange of 2 meters, were made 42 meters long, weighing 120 tons.

On December 19, 2005, the first beam was concreted, in a total of 1032 units produced, in a work of great technical complexity and that goes down in the history of Portuguese engineering.