1. Graduate Student, Dept. of Civil Engineering, Univ. of Sherbrooke, Sherbrooke, QC, Canada J1K 2R1.
2. Associate Professor, Dept. of Civil and Environmental Engineering, Rice Univ., Houston, TX 77005.
3. Professor, Dept. of Civil Engineering, Univ. of Sherbrooke, Sherbrooke, QC, Canada J1K 2R1.
4. Professor, Dept. of Civil Engineering, Univ. of Sherbrooke, Sherbrooke, QC, Canada J1K 2R1 (corresponding author).