1. Professor, School of Civil and Transportation Engineering, Guangdong Univ. of Technology, Guangzhou Higher Education Mega Center, Guangzhou 510006, China.
2. Ph.D. Candidate, School of Civil and Transportation Engineering, South China Univ. of Technology, Wushan Rd., Tianhe District, Guangzhou 510641, China.
3. Associate Professor, Dept. of Civil and Environmental Engineering, Univ. of Tennessee, 313 John D. Tickle Bldg., Knoxville, TN 37996 (corresponding author).