1. PhD Civil Engineer, Assistant Professor, Dept. of Concrete Technology, EPS Univ. of Burgos, Calle Villadiego s/n, 09001 Burgos, Spain (corresponding author).
2. Architect, Technical Manager, Fundación Eraiker, Casa Nao No 3, Barrio Alza, Postal Box 4022, 20080 San Sebastián, Spain.
3. PhD Civil Engineer, Assistant Professor, Dept. of Materials Science, ETSICCP Univ. of Cantabria, Avda. de los Castros s/n, 39005 Santander, Spain.
4. PhD Civil Engineer, Professor, Dept. of Materials Science, ETSIB Univ. of Basque Country, Alameda de Urquijo s/n, 48013 Bilbao, Spain.