Transportation Research Record: Journal of the Transportation Research Board, No. 2312, Transportation Research Board of the National Academies, Washington, D.C., 2012, pp. 34–45. DOI: 10.3141/2312-04 Department of Civil and Environmental Engineering, University of Windsor, Windsor, Ontario N9B 3P4, Canada. Current affiliation for J. Dahl: Lea Consulting Ltd., 625 Cochrane Drive, Suite 900, Mar...