1. Postdoctoral Research Associate, Dept. of Civil and Environmental Engineering, Lehigh Univ., Bethlehem, PA 18015 (corresponding author).
2. Bruce G. Johnston Professor of Structural Engineering, Dept. of Civil and Environmental Engineering, Lehigh Univ., Bethlehem, PA 18015.
3. Joseph T. Stuart Professor of Structural Engineering, Dept. of Civil and Environmental Engineering, Lehigh Univ., Bethlehem, PA 18015.