1. School of Civil and Environmental Engineering, Nanyang Technological University, Blk N1 B4c-10, Nanyang Avenue, SG 639798, e-mail: harnas@ntu.edu.sg
2. School of Civil and Environmental Engineering, Nanyang Technological University, Blk N1, 01b-36, SG, 639798 (Corresponding author), e-mail: chrahardjo@ntu.edu.sg
3. School of Civil and Environmental Engineering, Nanyang Technological University, Blk N1, 01c-80, Nanyang Avenue, SG 639798, e-mail: cecleong@ntu.edu.sg
4. Jing-Yuan Wang, Associate Professor, School of Civil and Environmental Engineering, Nanyang Technological University, Blk N1, 01b-35Nanyang Avenue, SG 639798, e-mail: jywang@ntu.edu.sg