1. Ph.D. Candidate, Dept. of Civil Engineering, Univ. of Thessaly, Pedion Areos, Volos 38334, Greece (corresponding author).
2. Retired, Professor, Dept. of Civil Engineering, Univ. of Thessaly, Pedion Areos, Volos 38334, Greece.
3. Assistant Professor, School of Architecture, National Technical Univ. of Athens, 42 Patision, Athens 10682, Greece.