The 18-KIP ESAL forecast is vitally important in determining the Structural Number Required (SNR) for flexible pavement and the Depth Required (DR) for rigid pavement. Attention should be placed on truck percentages, especially when there are high variations of truck traffic over a short period of time (i.e., 2-3 years). High truck factor percentages can contribute greatly to the reduction of the pavement life cycle. Proper attention to input and good engineering judgement should be used when developing the ESAL forecasting process steps shown in this chapter.
- Chapters
- 1. Introduction and Overview
- 2. Traffic Data Sources and Factors
- 3. Scoping for Project Traffic Foresting
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4. Forecasting with Travel Demand Models
- 4.1 Introduction
- 4.2 Corridor and Project Traffic Forecasting
- 4.3 Fundamentals of Travel Demand Models
- 4.4 Model Calibration and Validation
- 4.5 Model Assessment and Selection
- 4.6 Travel Demand Model Development and Application
- 4.7 Use of Model Outputs in Traffic Forecasting
- 4.8 Documentation of Traffic Forecast
- 5. Forecasting Without a Travel Demand Model
- 6. Directional Design Hour Volumes
- 7. Estimating Intersection Turning Movements
- 8. Equivalent Single Axle Load (ESAL) Forecasting
- 9. Project Traffic for Tolled Managed Lanes
- Appendix A
- Appendix B
- Appendix C
- Appendix D