1. Postgraduate Student, Dept. of Engineering Mechanics, Shandong Univ., Jingshi Rd., Jinan 250000, China.
2. Professor, Dept. of Engineering Mechanics, Shandong Univ., Jingshi Rd., Jinan, China (corresponding author).
3. Ph.D. Candidate, Dept. of Engineering Mechanics, Shandong Univ., Jingshi Rd., Jinan, China.
4. Lecturer and Postdoctoral Researcher, Dept. of Engineering Mechanics, Shandong Univ., Jingshi Rd., Jinan, China.