1. Associate Professor, Dept. of Civil Engineering, Univ. of Castilla–La Mancha, 13071 Ciudad Real, Spain (corresponding author).
2. Professor, Dept. of Applied Mathematics, Univ. of Cantabria, 39001 Santander, Spain.
3. Professor, Dept. of Construction and Fabrication Engineering, Univ. of Oviedo, 33203 Gijón, Spain.
4. Ph.D. Student, School of Civil Engineering, Polytechnic Univ. of Madrid, 28040 Madrid, Spain.