1. Professor and Assistant Dean, College of Civil Engineering and Architecture, Guilin Univ. of Technology, Guilin 541004, China.
2. Associate Professor, Dept. of Civil and Environmental Engineering, Michigan Technological Univ., 1400 Townsend Dr., Houghton, MI 49931 (corresponding author).
3. College of Civil Engineering and Architecture, Guangxi Univ., 100 University Rd., Nanning, Guangxi 530004, China.