1. Ph.D. Student, Dept. of Civil and Environmental Engineering, Univ. of Waterloo, Waterloo, ON, Canada, N2L 3G1.
2. Professor and Canada Research Chair, Dept. of Civil and Environmental Engineering, Univ. of Waterloo, Waterloo, ON, Canada, N2L 3G1 (corresponding author).
3. Distinguished Professor Emeritus, Dept. of Civil and Environmental Engineering, Univ. of Waterloo, Waterloo, ON, Canada, N2L 3G1.