1. Graduate Research Assistant, Dept. of Civil, Construction, and Environmental Engineering, Iowa State Univ., Ames, IA 50011-3232 (corresponding author).
2. Professor, Dept. of Civil, Construction, and Environmental Engineering, Iowa State Univ., Ames, IA 50011-3232.
3. Associate Professor, Dept. of Civil, Construction, and Environmental Engineering, Iowa State Univ., Ames, IA 50011-3232.