1. School of Civil and Resource Engineering; University of Science and Technology Beijing; Beijing 100083 China
2. Department of Civil and Environmental Engineering; University of Illinois at Urbana-Champaign; Urbana IL 61801 USA
3. National Center for Materials Service Safety; University of Science and Technology Beijing; Beijing 100083 China
4. Research Center of Structural Monitoring and Control, School of Civil Engineering; Harbin Institute of Technology; Harbin 150090 China