1. Geotechnical and Structural Engineering Research Center, Shandong University, Jinan 250061, China.
2. College of Marine Science and Biological Engineering, Qingdao University of Science and Technology, Qingdao 266042, China.
3. School of Mathematics, Shandong University, Jinan 250100, China.
4. School of Engineering Medicine, Beihang University, Beijing 100083, China.