1. Ph.D. Candidate and Research Assistant, Dept. of Civil and Environmental Engineering, Michigan Technological Univ., Houghton, MI 49931-1295.
2. Professor, Dept. of Civil and Environmental Engineering, Michigan Technological Univ., 1400 Townsend Drive, Houghton, MI 49931-1295 (corresponding author).
3. Assistant Professor, Civil Engineering Dept., College of Engineering, California Baptist Univ., 8432 Magnolia Ave., Riverside, CA 92504.