Reflective Cracking Prevention 1

[LCruiser]

I'm trying to find information on reflective cracking control with Superpave pavements. I have heard that Superpave, because of its more consistent properties while cold and improved properties in tension, reduces the rate of reflective cracking but can't find anything on it. Does anybody know the difference between Marshall and Superpave mixes as far as that?

Thanks in advance...

 

[Ron]

Both will eventually reflect cracks. Just because the design is done using a different method doesn't change the fact that you still have the same AC, aggregate, and other conditions.

 

[LCruiser]

I agree they will both eventually crack. However, is there an order of magnitude difference between the time required?

As I understand it, reflective cracking happens when it's coldest and the AC is most brittle (as in right now, by the way - where's that global warming when you need it?).

It's not the same AC. Superpave mix viscosities are more consistent through wide temperature ranges. Therefore, it seems to me that it would have to be much colder for the cracks to come through, or the cracks would propogate more slowly. We haven't been using it long enough for any cracking to come through, that I know of.

 

[Ron]

My point about the same materials is that once the initial rheological properties of the asphalt are equilibrated by volatization/weathering, they both act about the same.

Will it take longer for the Superpave mix to allow reflective cracking....possibly, but that depends on the mix, the time of year it is placed, the activity of the original cracks, and the weather.

You would not be looking at "orders of magnitude" differences.