1. Ph.D. Candidate, School of Railway Engineering, Iran Univ. of Science and Technology, Tehran 19818-78181, Iran (corresponding author).
2. Associate Professor, School of Railway Engineering, Iran Univ. of Science and Technology, Tehran 16846-13114, Iran.
3. Professor, School of Railway Engineering, Iran Univ. of Science and Technology, Tehran 16846-13114, Iran.
4. Professor, Dept. of Civil Engineering, Sharif Univ., Tehran 11365-8639, Iran.
5. School of Railway Engineering, Iran Univ. of Science and Technology, Tehran 18941-58567, Iran.