1. Graduate Student, Dept. of Civil and Environmental Engineering, Univ. of Alberta, Edmonton AB, Canada T6G 2G7.
2. Professor, Dept. of Civil and Environmental Engineering, Univ. of Alberta, Edmonton AB, Canada T6G 2G7 (corresponding author).
3. Professor Emeritus, Dept. of Civil and Environmental Engineering, Univ. of Alberta, Edmonton AB, Canada T6G 2G7.