1. School of Civil Engineering, Central South University, NO.22 Shaoshan South Road, Changsha 410075, China
2. School of Civil Engineering, National Engineering Laboratory for High Speed Railway Construction, Central South University, NO.22 Shaoshan South Road, Changsha 410075, China
3. Yunnan Science Research Institute of Communication Co., Ltd., NO.9 Shijia Lane Tuodong Road, Kunming 650011, China