The viaduct over the Xunclà river has a total length of 220m and it is placed in the AP-7 Highway between la Jonquera-Salou cities, stretch Fornells-Vilademuls. Spans: 35.6m+ 4×37 m+ 35.6m. Depth of the beams: 1.50m + concrete compression slab of 0.23 m depth.

This project is about the widening of the AP-7 Highway from 2 to 3 lanes for each way. In order to do that, the new piers are executed in the outer sides and in the median strip of the existing lanes. So, in each section there are 3 new piers plus 2 existing piers. The new part of the deck is done by 2 “U” beams placed on the new outer piers and by 4 “I” precast beams placed on the new central pier. The concrete slab is placed at the top of the beams, with the particularity of leaving a longitudinal joint on the new part of the median strip, in order to make independent one way direction to the other way.

The piers foundation is direct in some cases and by piles in other cases.

It is noteworthy that the viaduct is located in an area of moderate seismic activity, with basic soil acceleration a = 0.09g, this action has being decisive in the design of many elements of the structure.

The splitting of the viaduct project also includes a reinforcement for the existing piers in order to adapt the to the current Spanish Code. It consists of connecting four reinforcement ribs to the existing piers using rebars.

It is also important to remark that a shallow footing has been designed to join the new piers (using deep foundation) with the existing piers (using shallow foundation). The connection has been done with prestressed bars.

The aim of this connection is that part of the forces over the existing piers can be transmitted to the new foundation. So, there is no necessity to reinforce the existing piers below the shallow footing.