1. Lecturer, Zijin School of Geology and Mining, Fuzhou Univ., Fuzhou 350108, China; Key Laboratory of Geohazard Prevention of Hilly Mountains, Ministry of Natural Resources, Fuzhou 350002, China; Fujian Key Laboratory of Geohazard Prevention, Fuzhou 350002, China.
2. Research Assistant, College of Civil Engineering, Fuzhou Univ., Fuzhou 350116, China.
3. Professor, School of Civil and Environmental Engineering, Nanyang Technological Univ., Blk N1, 50 Nanyang Ave., Singapore 639798 (corresponding author).