1. Structural Engineer, Structural Dept., McCormick Rankin Corp., Mississauga, ON, Canada N5K 2P8.
2. Associate Professor, Dept. of Civil and Environmental Engineering, Univ. of Waterloo, Waterloo, ON, Canada N2L 3G1.
3. Professor and Canada Research Chair, Dept. of Civil and Environmental Engineering, Univ. of Waterloo, Waterloo, ON, Canada N2L 3G1 (corresponding author).