1. School of Earth Sciences and Engineering, Nanjing University, Nanjing 210023, China
2. China Railway Shanghai Group Co., Ltd., Shanghai 200071, China
3. College of Civil Engineering, Tongji University, Shanghai 200092, China
4. Traction Power State Key Laboratory, Southwest Jiaotong University, Chengdu 610031, China
5. Department of Civil and Environmental Engineering, University of Illinois at Urbana-Champion, Urbana, IL 61801, USA