1. Associate Professor, Dept. of Civil Engineering, National Taiwan Univ., Room 313, Civil Engineering Bldg., No. 1, Roosevelt Rd., Sec 4, Taipei 10617, Taiwan (corresponding author).
2. Graduate Research Assistant, Dept. of Civil Engineering, National Taiwan Univ., Room 313, Civil Engineering Bldg., No. 1, Roosevelt Rd., Sec 4, Taipei 10617, Taiwan.
3. Assistant Research Scientist, Civil, Hydraulic Engineering and Railway Transportation Research Center, Sinotech Engineering Consultants, Inc., No 280, Xinhu 2nd Rd., Neihu District, Taipei 11494, Taiwan.