Superpave

[Skyenew]

Hi, I'm doing some research to determine if a territorial government in northern Canada should consider switching from traditional Marshall mix to Superpave. We have logistics constraints due to our isolation and limited population base. I've done tons of reading, but curious to hear from others who went through the change over. Did anyone have success with a phased approach (PG binders with Marshall aggregate specs and testing)? What is the big difference between Superpave aggregates and Marshall aggregates?

Thanks,

 

[Ron]

The Marshall Method of mix design has a long history of good performance. I have not yet seen a significant advantage of the Superpave approach over the Marshall method. After all, they both use aggregate, filler, and asphalt cement.....not much magic there.

 

[BigH]

The magic is getting it all to work in unison for a good pavement! - without flushing, rutting, cracking, etc. I feel that the Marshall is a good way to go subject to proper choices of the binder, air voids, compaction levels.

 

[Skyenew]

Marshall mix had worked in the past for us, but the reason we're looking into PG binders is because of low temperature thermal cracking. The PG binders should eliminate the thermal cracking, but is it worth all the fuss of switching over?

 

[BigH]

Why not use Elvaloy or some other polymer for low temp?

 

[ACtrafficengr]

Mostly out of curiosity, I searched the US Army Corps of Engineers' Cold Regions Research Engineering Lab's site, and found a few citations for you:

[ul]
[li]Wegman, Dan (Koch Materials Company, Saint Paul, MN); Weigel, Jack and Forsberg,Alan.
Evaluations of low temperature Superpave PG asphalt binders: in Proceedings of the Forty-sixth annual conference of the Canadian Technical Asphalt Association (Thompson, Elaine, editor), Polyscience Publications, Laval, PQ, Canada, p. 1-11 (French sum.), illus. incl. 2 tables, 12 ref., 2001. Meeting: Nov. 17-21, 2001, Toronto, ON, Canada. [/li]


[li]Superpave vs the Canadian winter; low temperature performance at C-SHRP test roads: in Compendium; cold temperature asphalt pavement cracking in Canada (Thompson, Elaine, editor), Polyscience Publications, Laval, PQ, Canada, p. 235-243, illus. incl. 1 table, 3 ref., 2001.[/li]
[/ul]

------------------------------------------
"Come to think of it, there are already a million monkeys typing on a million typewriters, and the Usenet is NOTHING like Shakespeare.

- Blair Houghton

 

[BigH]

You might want to contact Lynn Irwin at Cornell University; he is/was a consultant at the Cold Regions Research Centre.

 

[GabionGuy]

Skyenew,

While not connected to Superpave, you may want to research a pavement reinforcement called RoadMesh. It is a 3D reinforcement used in asphalt pavements that will confine the asphalt and increase the performance. I don't know if it has been used in very cold climates (Arctic Regions).

 

[ACtrafficengr]

I'll second the recommendation of Dr. Irwin at the Cornell Local Roads Program. If he doens't know the answer, it's likely he'll know somebody that does.

------------------------------------------
"Come to think of it, there are already a million monkeys typing on a million typewriters, and the Usenet is NOTHING like Shakespeare.

- Blair Houghton

 

[BigH]

ACtrafficengr - you a Cornell grad too?? -oooppps

 

[ACtrafficengr]

Nope, a former CLRP employee.

------------------------------------------
"Come to think of it, there are already a million monkeys typing on a million typewriters, and the Usenet is NOTHING like Shakespeare.

- Blair Houghton

 

[stubbypaul]

The PG binder is truly an advantage to use in severe temperature changes, We use it in Utah extensively along with Superpave mixes, however a PG oil blended in Marshall type mixes works well if the aggregate is 100% crushed, this is one of the main keys to a good asphalt matrix whether it's Superpave or Marshall, both design types have there advantages based upon the use.