1. School of Transportation Civil Engineering, Shandong Jiaotong University, Jinan 250357, China
2. Department of Civil and Industrial Engineering, University of Pisa, Largo Lucio Lazzarino, 56122 Pisa, PI, Italy
3. School of Highway, Chang’an University, South 2nd Ring Road Middle Section, Xi’an 710064, China
4. Department of Civil Engineering, Aalto University, 02150 Espoo, Finland