Shahab Karimifard1, Mohammad Reza Alavi Moghaddam2. 1. Department of Civil and Environmental Engineering, Amirkabir University of Technology (Tehran Polytechnic), Hafez St., Tehran 15875-4413, Iran; Department of Civil Engineering, University of Nebraska-Lincoln, Lincoln, NE 68583, United States. 2. Department of Civil and Environmental Engineering, Amirkabir University of Technology (Tehran Polytechnic), Hafez St., Tehran 15875-4413, Iran. Electronic address: Alavi@aut.ac.ir.