Porto Light subway

It is often thought that there is only one type of metro, the one that is most common in a country's major centres. But this is not the case, there are several, and one of these types is the 'light rail'.

Unlike the more traditional metros, it has a lower hourly capacity and smaller trains. But that does not mean it is easier to build.

A striking example is the light metro in Porto, which extends over a network of four lines, covering a large catchment area of around two and a half million inhabitants and a total of 73 km of track, 36% of which is double track. Its construction was a complex challenge, in particular due to the development of tunnels in densely populated urban areas and the need to carefully monitor possible subsidence.

To meet this challenge, it was necessary to use mechanised excavation with Earth Pressure Balance technology to ensure the stability of the structures during tunnel construction. In addition, the construction of the stations added further complexity to the project, with eleven underground stations, each with different characteristics in terms of size and construction techniques.

Easy, yes, but not to be underestimated!