1. Graduate Research Assistant and Ph.D. Fellow, School of Civil Engineering, Engineering Campus, Universiti Sains Malaysia, 14300 Nibong Tebal, Penang, Malaysia.
2. Professor, School of Civil Engineering, Engineering Campus, Universiti Sains Malaysia, 14300 Nibong Tebal, Penang, Malaysia (corresponding author).
3. Dept. of Civil Engineering, Politeknik Sultan Azlan Shah, Behrang Stesyen, 35950 Behrang, Perak, Malaysia.
4. Associate Professor, School of Civil Engineering, Engineering Campus, Universiti Sains Malaysia, 14300 Nibong Tebal, Penang, Malaysia.