The future station of the Spanish high speed line in Girona is a diaphragm wall enclosure about 600 meters long, 55 meters wide and a digging depth of 25 meters.

The station is oriented north-south aligned with the current viaduct of the railway line that is one of the only two railway connections between Spain and France.

During its execution, some changes of the original project were accepted resulting in a completely different cross section compared with the original one. Thus, the station hosts a bus station and two storages of parking for vehicles, and high-speed station, constituting an intermodal station.

The different slabs are supported on the exterior diaphragm walls and the central piers of the station leading to three enclosure or spans: the park side enclosure, the enclosure next to the viaduct and the central enclosure.

For timing reasons, the tunnel boring machine (TBM) that performed the tunnel before and after the station had to go through it when the entire station had not been finished yet. That was the reason for constructing the pile wall in the lineup of the piles. So, it was possible to excavate only the central enclosure from the level of the first parking and thus not to delay the pass of the TBM. Later, the side enclosures were excavated.

The pile wall executed for the provisional construction phase of the TBM passing along the station is demolished to the lower bound of the counter-vaults, anchoring them in order to resist the uplift because of the water pressure.

The external diaphragm walls of the enclosure are about 45 meters length and executed with hydromill. The slabs are waffle slabs with a depth ranging from 1.20 to 0.80 m and executed with presstressed concrete. They are supported in the internal piers and the external diaphragm walls.

This solution enables to resist the uplift due to the large water pressure without having to increase the weight of the structure, but using the friction with the ground in the external diaphragm walls and the internal piles. Then the diaphragm walls are useful during the excavation and the final structure.

Bridge Technologies has worked with the contractor company during the phases of the study of alternatives and its subsequent development up to the last detail, including the study of all phases of construction and carrying out all the engineering for the construction.

A structurally efficient and economically optimal solution for both, the contractor company and the administration, was achieved