The base tunnel -25km-long, double tube- is the principal work of the “Pajares railway alternate route” and will cross the “Cantabric Cordillera” between Leon and Asturias. The length of the railway connection will be reduced from 83 to 50km.
Owner:JV INECO–Geoconsult for Ministerio de Fomento
Period of activity:2001-2003
Description of the works:The tunnel has double-tube with underground preferential stop point. Entrance from the North portal and intermediate access tunnels were foreseen. The tunnels are connected by by-passes every 400m. The boring was carried out using TBM internal diameter 10.40. Due to the difficulties expected, the central segment has been excavated following traditional techniques (for about 6.5km in total from two intermediate accesses and 3 advancement fronts per each section) like the initial section from the North entrance (4.0km).
Geodata activity:Independent Expert Advice for the INECO-GEOCONSULT Consortium: feasibility study with the analysis of 9 alternative alignments to overpass Cordigliera Cantabrica with crossing road tunnel between km 25 and 34; comparative analysis of the two segments (P20BH and P20BPH); analysis of the development proposals for the project; consultancy in the geotechnical campaign; identification of the optimal construction process; identification of the aspects to be highlighted during the future tender stage; multi-criteria analysis.