1. 22 nd Conference Roads and Works - 2014 Asphalt Trial – Outcomes so far Rod Ellis Board Member IPWEA SA

2. Binder Filler Aggregate What is Asphalt?

3. Light Vehicles No heavy turning Less 5E10^5 ESA Low Volume Roads

4. Lower air voids needed to slow oxidation Why the Trial ? Higher Binder needed to resist water penetration

5. Because we need to slow aging process

6. Linden et al (1989) “Asphalt pavement life is reduced by 10% for each % increase in voids above 7%” Oliver 1992 “Ageing of binder greatly reduces for mixes that are compacted to 6% air voids and below” APRG technical noted light duty non structural asphalt surfaces and overlays (July 1997) Aims: Low air voids (density) High bitumen content (impermeability)

7. Target 4-6% field air voids Goal of trial

8. Local Government Research and Development Scheme 2012 Led by The City of Salisbury with additional funding by the following Councils: City of Salisbury City of Burnside City of Playford City of Port Adelaide Enfield West Torrens City Council Adelaide Hills Council City of Adelaide City of Unley City of Marion Light Regional Council IPWEA SA

9. Collaborative Contribution of Expertise

13. A: C320 B: C320 WMA C: C170 RAP D: C170 RAP WMA

17. TABLE 4.3(a) MIX PROPERTIES OF FINE DENSE MIX ASPHALT CHARACTERISTICFineAC7FineAC10FineAC14 Nominal Mix Sieve Size (mm)6.79.513.2 Minimum Binder Content (%)6.05.75.2 Production Air Voids (%) (@ 50 cycles) Production Air Voids Tolerance (%) 4.0 3.0 – 5.5 4.0 3.0 – 5.5 4.5 3.5 – 6.0 Target In-situ Air Voids (%) Binder Film Index (µm) Minimum 2.0 – 5.0 8.0 3.0 – 7.0 8.0 4.0 –7.0 8.0

18. http://www.dpti.sa.gov.au/contractor_documents/ specifications_-_division_2_roadworks Fine AC mix DPTI – Part 227 and 228 – Fine AC mix

19. More filler More binder More workable More surveillance What did we learn? Low voids High voids

20. Field Void (%)3%4%5%6%7%8%9%10%11% Possible Life (yr)433935322926242220 Field Voids range 3-6%Field Voids (Average 6.5-7.5) - range 5.5-10% TargetCurrent Practice

21. 2014 LGA R&D Application 15 sites - Fine AC 10 WMA and RAP Laboratory Testing Durability Next step?

22. Road Surface Management Field and Accounting Treatment

23. Accounting Consideration What defines the surface asset – Top surface – Multilayered surface (componentised?) Surface Type – Hotmix, Spray Seal, Slurry End of Life – Resurface no preparation – Resurface with patching – Resurface with pavements rejuvenation

25. Intergenerational Consideration Examples – Hotmix every 25 years( high voids) – Hotmix every 40 years (low voids) – Hotmix then after 40year spray seal – Spray seal every 20 year Factors – Double and single – Edge profile cost or full width profile – Hotmix Field voids linked to life

26. 100 year Renewal Cost alternatives for a typical street YearHotmix 25yearHotmix 40 year Hotmix 40 year then seal 25 yr seal 20 yr 0 $ 22,848.00 $ 23,583.00 $ 16,000.00 10 20 $ 9,600.00 30 $ 28,448.00 40 $ 29,183.00 $ 9,600.00 50 $ 34,048.00 60 $ 16,000.00 $ 21,600.00 70 $ 28,448.00 80 $ 34,783.00 $ 9,600.00 90 100 $ 34,048.00 $ 9,600.00 $ 147,840.00 $ 87,549.00 $ 58,783.00 $ 76,000.00

27. 100 year Renewal Cost Alternative

28. WOL – Discounted Annual Cashflow 4% discount rate

29. State Built up Low Volume Sealed network – 7640km (27 Councils) Large Centre‘s

30. Rejuvenation ( management option for high void asphalt ?)

31. Possible 100yr cost profile with Rejuvenation( typical Street) YearHotmix 25yearHotmix Rejuvenate 0 $ 22,848.00 $ 22848.00 10 $ 5280.00 20 30 $ 28,448.00$ 5280.00 40 $ 28448.00 50 $ 34,048.00 60 $ 5280.00 70 $ 28,448.00 80 $ 34,048.00 90 $ 5280.00 100 $ 34,048.00 $ 147,840.00 $ 111,744.00

32. The Size of Opportunity Councils with Large Urban Road Networks – 7640km, 27 Councils – Adopt low void hotmix (Fine AC) – Adopt a WOL strategy including all treatment options to extend AC life – Annual saving over $10Million to the state Councils with Small and Remote Urban Roads – 2230km, 41 Council – Spray seal treatment selection critical

33. The Size of Opportunity Rural Road Network (outside Urban Centres) – 7400km, 68 Councils – Proactive Maintenance – Edge, Shoulder and drainage – Early intervention for resealing Note – many roads grant funded for construction but renewals are funded by council.

34. Products Polymer Micro surfacing Rejuvenation AC10M, Fine AC10 C320,C170 WMA RAP

35. 22 nd Conference Roads and Works - 2014 To Spray or Not to Spray Rod Ellis, Board Member IPWEA SA Peter Levett - City of Salisbury Kelly Manning - AAPA