1. Ph.D. Candidate, Dept. of Civil and Environmental Engineering, Amirkabir Univ. of Technology, 15875-4413 Tehran, Iran.
2. Associate Professor, Dept. of Civil and Environmental Engineering, Amirkabir Univ. of Technology, 15875-4413 Tehran, Iran (corresponding author).
3. Associate Professor, School of Railway Engineering, Iran Univ. of Science and Technology, 16846 Tehran, Iran.