1. Graduate Research Assistant, School of Civil Engineering, Purdue Univ., West Lafayette, IN 47907.
2. Assistant Professor, School of Civil Engineering, Purdue Univ., West Lafayette, IN 47907 (corresponding author).
3. Olson Distinguished Professor, School of Civil Engineering, Purdue Univ., West Lafayette, IN 47907.
4. Consultant, 17035 NE 28th Place, Bellevue, WA 98008.