Abdalajis East | Spain

Completed in: 2007

Successful completion of the “impossible” tunnel on the Cordova-Malaga High Speed line; this is thanks to the development of a new design for the TBM that will be replicated in many projects around the world.

The Spanish construction giant, Dragados, chose SELI Overseas as a specialist partner for the execution of this project with TBM, for the most part developed in clay-rich, squeezing ground conditions that many technicians and university environments considered impossible to deal with using TBM.

For this challenge, SELI Overseas developed a double shield TBM with highly conical, short shields, also equipping the machine with advanced soil pre-treatment systems.

Although the formations crossed were fully in line with expectations in terms of instability and deformations, the TBM was able to overcome all the difficulties encountered and drilled the tunnel within the contracted timeframe, with a level of technical success that set the standard in the world of mechanised excavation.