1. Ph.D. Researcher, Dept. of Natural Resources and Environmental Engineering, School of Mining Engineering, Univ. of Vigo, Maxwell s/n, 36310 Vigo, Spain (corresponding author).
2. Postdoctoral Researcher, Dept. of Materials Engineering, Applied Mechanics and Construction, Univ. of Vigo, School of Industrial Engineering, Torrecedeira 86, 36208 Vigo, Spain.
3. Professor, Dept. of Natural Resources and Environmental Engineering, School of Mining Engineering, Univ. of Vigo, Maxwell s/n, 36310 Vigo, Spain.