1. Ph.D. Graduate, Dept. of Civil and Environmental Engineering, Univ. of Auckland, Private Bag 92019, Auckland Mail Centre, Auckland 1142, New Zealand (corresponding author).
2. Associate Professor, Dept. of Engineering Science, Univ. of Auckland, Private Bag 92019, Auckland Mail Centre, Auckland 1142, New Zealand.
3. Professor, Dept. of Civil and Environmental Engineering, Univ. of Auckland, Private Bag 92019, Auckland Mail Centre, Auckland 1142, New Zealand.