State of Canadian Technology: Challenges and Solutions in Western Canada

1. CUPGA 2008 Western Canada Perspective on State – of - the Canadian Technology Challenges and Solutions John Berti, P. Eng. bertij@huskyenergy.com

2. Western Canada (WCAN) • Conservative approach to the adoption of the Superpave system wrt to asphalt binder specifications and mixture design and analysis system • Marshall method is still the preferred system of choice including traditional pen/viscosity graded binders • Dense fine graded mixtures are most widely specified • Minimal percentages of RAP are allowed in most mixes • Very little use of SMA’s for high performance pavements

3. Superpave Performance Grade Binders • “Straight run” asphalts • WCAN Continues to Use Penetration grades • (based on CGSB Pen-Viscosity system) • PG grades are never or rarely specified • Small amounts of PG58-31

4. Superpave Performance Grade Binders • Modified Asphalts – (PG = modified) • Almost all modified demand uses PG specs • Approx. 7 different grades (from PG76-28 to PG58-37) • more commonly used in high service applications (traffic intersections and slow / high truck volume applications, new construction) • Alberta biggest user, Sask/Man lowest • No “PG plus” specs but AASHTO M320 Table 2 is occasionally specified • Alternative bids with life cycle cost adjusts sometimes used (ie 150/200A or PG 58-34)

5. Superpave Performance Grade Binders • Usage of PG grades has been increasing slightly • Approx 6% of paving asphalts in Western Canada are specified using PG specifications • P3’s are a big factor – contractors making the decision

6. Superpave Performance Grade Binders • Issues & Challenges • Concerns about allowing lower performing grades • Concerns about available grade selection • Future changes • No switching to PG for straight runs in near term • BC – increased use of PG 70-22

7. Superpave Mixes • Used occasionally in BC (Vancouver area) (improved rut resistance) but minimal usage in other WCAN provinces • In the past many Alberta highway projects used Superpave mix specifications but usage today has dropped • Overall estimate less than 10% of Western Canada mixes are using Superpave mix specifications.

8. Superpave Mixes • Issues & Challenges • High aggregate costs and greater pit depletion • AB - Concerns about poorer performance especially with coarser mixes • No big changes expected in the near term

9. Stone Mastic Asphalts • City of Edmonton has had extensive experience and use as a regular part of their program. Usage is expected to increase slightly. • Other jurisdictions (Alberta and BC) have done some SMA trials or projects and others (Sask/Man.) have not.

10. Stone Mastic Asphalts • Issues & Challenges • Edm - Availability of zero grind (mineral filler) • High Quality aggregates expensive to import, mix design, AC drain down, getting good lay down • Future changes • Other than Edm. usage of SMA is expected to stay about the same • Edm. using cement to replace zero grind • Edm. looking at smaller max. size aggregate

11. Other Activities • Warm mix • Many jurisdictions are doing warm mix trials and a number of different technologies have been used • Rubber Crumb • Used extensively throughout Alberta over last 5 years but a number of agency’s have expressed performance concerns • Usage in Alberta in future is questionable • Trials have been done in BC and Sask as well. • Other emerging technologies over the last 5 years include: • Ultra thin lift overlays, foamed asphalt stabilized base course, recycled asphalt shingles

12. Thank You !