Estimating Cumulative Traffic Loads, Final Report for Phase 1

2000Richter, Cheryl AllenWork was conducted as part of the LTPP Data Analysis Technical Support Contract.PDFTech ReportFHWA-RD-00-054DTFH61-96-C-00003Axle loadsDesign methodsTypes of pavements by surface load distributionPavementsMathematical modelsAsphalt pavementsConcrete pavementsTrafficSensitivity analysisTraffic loadsLoad-related distress prediction modelsLong Term Pavement PerformanceLTPPNorth AmericaUnited States. Federal Highway Administration. Office of Infrastructure Research and DevelopmentHajek, J. J.Selezneva, O. I.Selezneva, Olga I.ERES Consultants, Inc.NTL-HIGHWAY/ROAD TRANSPORTATION-Pavement Management and PerformanceFederal Highway AdministrationThe knowledge of traffic loads is a prerequisite for the pavement analysis process, especially for the development of load-related distress prediction models. Furthermore, the emerging mechanistically based pavement performance models and pavement design methods (such as the anticipated 2002 Pavement Design Guide) require the knowledge of the load spectra acting on the pavement during its lifespan.This report describes a procedure for obtaining axle load spectra for Long Term Pavement Performance (LTPP) sections. The procedure has been demonstrated and evaluated by applying it to 12 LTPP sections for which different amounts of monitoring traffic data were available. Typically, for the majority of LTPP sections, there are only a few years for which the traffic load data were collected by automated equipment in the mid-1990s. To obtain axle load spectra for all in-service years, traffic loads must be projected: backcasted (for the years before the installation of traffic monitoring equipment) and forecasted (for the years after the automated equipment no longer provides data)