1. Ph.D. Student, School of Civil Engineering, Institute of Smart Materials and Structures, Beijing Jiaotong Univ., Beijing 100044, China.
2. Senior Lecturer, Dept. of Mechanical Engineering, Univ. of Auckland, 20 Symonds St., Auckland 1010, New Zealand.
3. Professor, School of Civil Engineering, Institute of Smart Materials and Structures, Beijing Jiaotong Univ., Beijing 100044, China (corresponding author).