1. Professor, Dept. of Civil Engineering, Universidad Católica de Colombia, Bogotá D.C., Colombia.
2. Ph.D. Student, Dept. of Civil Engineering, Universidad Industrial de Santander, Bucaramanga, Santander.
3. Professor, School of Civil Engineering, Pontificia Universidad Católica de Valparaíso, Valparaíso, Chile.
4. Professor, School of Civil Engineering, Universitat Politècnica de València, Valencia, Spain.