1. Graduate Research Assistant, Dept. of Civil, Construction and Environmental Engineering, Iowa State Univ., Ames, IA 50011.
2. Research Associate, School of Civil Engineering, National Technical Univ. of Athens, Athens, Greece.
3. Assistant Professor, Dept. of Civil, Construction and Environmental Engineering, Iowa State Univ., Ames, IA 50011 (corresponding author).
4. Assistant Professor, School of Civil Engineering, National Technical Univ. of Athens, Athens, Greece.