1. Civil Engineer, Dept. of Civil Engineering, Univ. of Calabria, Arcavacata di Rende, Via P. Bucci, Cosenza 87036, Italy.
2. Assistant Professor of Civil Engineering, Facultad de Ingeniería, Univ. de la Sabana Campus Univ. del Puente del Común, km 7 Autopista norte de Bogotá, Chía, Cundinamarca 250001, Colombia (corresponding author).