Jacked underpasses in Radial 4 motorway. Madrid, Spain

For the crossing of two ramps of an interchange at Radial 4 motorway under a railway in Madrid it was necessary to design underpasses built using the jacking method.

This method consists of the construction of the underpass in a position just next to the embankment and progressively jacking and excavating until reaching the final position, with the railway fully operational during the complete process.

One underpass is 80 m long while the other is 60 m long. Both have an inner width of 16 meters.

SILGA has been responsible for the concept and detail design of the structure. That has included the design of the construction slab and reaction wall. SILGA also did assistance during construction.

Client is Ferrovial Construction, and Owner the Ministry of Works, in Spain.