1. Assistant Professor III, Brazil Departamento de Engenharia de Transportes, Universidade Federal do Ceará, Campus do Pici, Bloco 70360, Fortaleza, Ceará 455-760, Brazil.
2. Research Assistant, Brazil Departamento de Engenharia de Transportes, Universidade Federal do Ceará, Campus do Pici, Bloco 70360, Fortaleza, Ceará 455-760, Brazil.
3. Assistant Professor, Civil Engineering Dept., School of Engineering, Porto Univ., Rua Dr. Roberto Frias, 4200-465 Porto, Portugal (corresponding author).