Fleet replacement modeling : final report, July 2009.

691271061PDFTech ReportFHWA-OR-RD-10-01Vehicle fleetsMaintenanceEquipment replacementOregonOregon. Dept. of Transportation. Research SectionKim, David S.Porter, J. DavidKriett, PhillipMbugua, WilsonWagner, TristanOregon State University. School of Mechanical, Industrial and Manufacturing EngineeringNTL-PLANNING AND POLICY-PLANNING AND POLICYUS Transportation CollectionThis project focused on two interrelated areas in equipment replacement modeling for fleets. The first area was research-oriented and addressed a fundamental assumption in engineering economic replacement modeling that all assets providing a similar service are equally utilized. It is shown that if assets providing a similar service are not equally utilized, than overall operational costs of a fleet increases. The second area addressed the need of the Oregon Department of Transportation (ODOT) Fleet Services Section for a modern, user-friendly, well constructed and documented fleet condition model. The state-of-the-art in equipment replacement modeling and the research on effective prioritization measures computable from existing data is discussed. A new model is developed utilizing the highest value of (Age/Age standard)+(Usage/Use standard) as a measure to prioritize equipment. The model is described and it is shown through simulation that the prioritization measure utilized performs better than several other suggested measures. This project was conducted jointly with the ODOT Fleet Services Section and the ODOT Research Section