1. The Civil Engineering College of Hunan University; No. 2 Lushan South Road, Yuelu District Changsha 410082 P.R. China
2. Department of Civil and Architectural Engineering; City University of Hong Kong; Tat Chee Avenue, Kowloon Hong Kong 999077 P.R. China
3. Department of Building Engineering of Hunan Institute of Engineering; Xiangtan 411101 P.R. China