1. Professor, Key Laboratory of Building Safety and Energy Efficiency (Ministry of Education), College of Civil Engineering, Hunan Univ., Changsha 410082, China (corresponding author).
2. Ph.D. student, Key Laboratory of Building Safety and Energy Efficiency (Ministry of Education), College of Civil Engineering, Hunan Univ., Changsha 410082, China.
3. Research Associate, Division of Civil Engineering, Univ. of Dundee, Dundee DD1 4HN, UK.