1. Graduate Student, Graduate Program in Civil and Environmental Engineering, Univ. of Passo Fundo, BR 285, 99052-900 Passo Fundo, Brazil.
2. Lecturer, Environmental Engineering, Univ. of Passo Fundo, BR 285, 99052-900 Passo Fundo, Brazil.
3. Professor, Graduate Program in Civil and Environmental Engineering, Univ. of Passo Fundo, BR 285, 99052-900 Passo Fundo, Brazil (corresponding author).
4. Associate Professor, Graduate Program in Civil and Environmental Engineering, Univ. of Passo Fundo, BR 285, 99052-900 Passo Fundo, Brazil.
5. Professor, Dept. of Civil and Materials Engineering, Univ. of Illinois at Chicago, 842 West Taylor St., Chicago, IL 60607.