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The Project Team. Mike RileyLouw KannemeyerTom Van DamAlex Visser/Gerrie Van ZylGustav RohdeZulakmal bin SufianPeter Cenek. Limitations of HDM-III from the RDME viewpoint. HDM-III does not consider:Rigid pavementsMany types of flexible pavementsPavement texture and skid resistanceFreeze-th
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1. HDM-4: The Road Deterioration and Maintenance Effects Study
2. The Project Team Mike Riley
Louw Kannemeyer
Tom Van Dam
Alex Visser/Gerrie Van Zyl
Gustav Rohde
Zulakmal bin Sufian
Peter Cenek
3. Limitations of HDM-IIIfrom the RDME viewpoint HDM-III does not consider:
Rigid pavements
Many types of flexible pavements
Pavement texture and skid resistance
Freeze-thaw conditions
4. Other criticisms Heavily biased toward South American conditions
Empirically tied to specific
construction materials
environment
Ignores urban roads
5. Project Objectives Focus on areas not addressed in HDM-III
Little, if any, primary research
Consider available research and implement appropriate findings
Provide guidance on inputs and selection of calibration coefficients
6. Research Tasks 1010: Review of Experience
1020: Pavement Strength and FWD
1030: Rigid Pavement Models
1040: Extension of AC Models
1050: Maintenance Effects
1060: Texture Effects
7. Task 1010: Review of Experience Status: Draft issued at end of 1994
Reports from 45 countries were reviewed
Summarises pavement relationships of HDM-III
Presents calibrations used in other studies
Found wide use of HDM-III models but not a lot of guidance on new models
8. Task 1020:Strength and FWD In HDM-III, strength represented by SNC, modified Structural Number
Relationships provided between BB deflection and SNC for different materials
Widespread use of FWD has spurred the development of MSN-FWD relationships
9. Task 1020:Continued FWD has potential to provide more data in cost-effective manner Work by Gustav Rohde of South Africa has led to a proposed model of the following form: SN = a0 SIP HP