1. School of Civil Engineering, Fujian University of Technology, Fuzhou 350108, P. R. China
2. School of Civil Engineering, Chongqing University, Chongqing 400045, P. R. China
3. Department of Environmental Engineering, Ocean University of China, Qingdao, P. R. China
4. College of Science and Engineering, Flinders University, Adelaide 5001, Australia