1. Assistant Professor, North Dakota State Univ., Dept. of Construction Management and Engineering, NDSU Dept. 2475, Box 6050, Fargo, ND 58108-6050 (corresponding author).
2. Senior Lecturer, Univ. of Strathclyde, Dept. of Civil Engineering, 619 John Anderson, Glasgow, G1 1XQ, Scotland, UK.
3. Graduate student, NDSU, Dept. of Construction Management and Engineering, NDSU Dept 2475, Box 6050, Fargo, ND 58108-6050.
4. Graduate student, NDSU, Dept. of Construction Management and Engineering, NDSU Dept. 2475, Box 6050, Fargo, ND 58108-6050.