1. Assistant Professor, Structural Engineering Research Center, International Institute of Earthquake Engineering and Seismology, 19395 Tehran, Iran (corresponding author).
2. Managing Director, Institute of Continuum Mechanics, Univ. of Hannover, 30167 Hannover, Germany.
3. Assistant Professor, School of Civil Engineering, Univ. College of Engineering, Univ. of Tehran, 11365 Tehran, Iran.