1. Department of Bridge Engineering, School of Civil Engineering, Southwest Jiaotong University, Chengdu, Sichuan, China;
2. Key Laboratory of High-Speed Railway Engineering, Ministry of Education, Chengdu, Sichuan, China;
3. Department of Civil, Environmental and Ocean Engineering, Stevens Institute of Technology, Hoboken, NJ, USA;
4. Department of Civil, Architectural, and Environmental Engineering, Missouri University of Science and Technology, Rolla, MO, USA