1. Ph.D. Candidate, Dept. of Civil Engineering, National Cheng Kung Univ., Tainan 704, Taiwan.
2. Professor, Dept. of Civil Engineering, National Cheng Kung Univ., Tainan 704, Taiwan (corresponding author).
3. Associate Researcher, Public Construction Research and Development Center, National Cheng Kung Univ., Tainan 704, Taiwan.