1. PhD Candidate, Dept. of Civil Engineering, King Mongkut’s Univ. of Technology Thonburi, Bangkok 10140, Thailand. E-mail: vanchasata@hotmail.com
2. Associate Professor, Dept. of Civil Engineering, King Mongkut’s Univ. of Technology Thonburi, Bangkok 10140, Thailand (corresponding author). E-mail: chai.jat@kmutt.ac.th
3. Associate Professor, Dept. of Civil Engineering, King Mongkut’s Univ. of Technology Thonburi, Bangkok 10140, Thailand. E-mail: kraiwood.kia@kmutt.ac.th