gravel rolled into asphalt 1

[beryl10]

Hi,

I am wondering if it is possible to have gravel rolled into the surface of asphalt as its being installed. The purpose is simply for aesthetic reasons. I don't really like the look of a solid black driveway. I've looked into getting tar and chip, but, there are very few people who do that in my area. In fact, the only company I found that does, only installs it on an already paved surface. So, being its late in the season, I decided I'd get the asphalt driveway installed, and then could alaways at a later date, put down the chip seal.

One of the contractors I spoke with about the asphalt driveway, suggested rolling gravel into the surface of the asphalt immediately after it has been rolled out. Is this ever done? Does anyone have an opinion on this from both a structural and aesthetic standpoint? I'm thinking it may look like exposed aggregate surfaces in concrete. But, would the aggregate really get into the asphalt and stick without that layer of tar? And, if this is an ok thing to do, would it work better with one type of asphalt mix over another (fine surface layer vs a binder course)?

 

[ACtrafficengr]

I'm not sure you'd get good adhesion by rolling aggregate onto fresh hot mix.

Have you considered StreetPrint or it's competitors? It's not the exposed aggregate surface you're talking about, but it isn't plain asphalt, either.

"...students of traffic are beginning to realize the false economy of mechanically controlled traffic, and hand work by trained officers will again prevail." - Wm. Phelps Eno, ca. 1928

"I'm searching for the questions, so my answers will make sense." - Stephen Brust

 

[COEngineeer]

If you dont like the way it looks then get concrete. You can do a lot more with concrete (make it shiny, texture it, tile it, etc.)

 

[francesca]

Actually this is standard practise on the streets of London. The gravel is uniformly graded and is added during compaction. (Possibly before, I worked for the consultant, not the contractor, so I measured up more than I saw being paved, particularly as most of it was done at night.) It looks really good where they used red aggregate.

The best picture I could find on the internet is this one:

(click to enlarge).

 

[MikeHalloran]

You can lighten the color of asphalt considerably by dusting it with cement. Mist some water on, then a little more cement.

Yeah, I thought it would wash off, too. It only lasted thirty years.



Mike Halloran
Pembroke Pines, FL, USA

 

[BigH]

Francesca is correct - this was/is standard asphalt construction on UK roads. Ref: Hunter "Bituminous Mixtures in Road Constrution" Thomas Telford 1994. It surprised me as I've not seen in N.A.

 

[Prepakt1]

Gravel can be rolled into asphalt driveways with good results.The quantity has to be carefully monitored. If you add too much gravel red or white you will ruin the surface of the asphalt. I would recommend that the surface be no more than about 5% gravel by area. the best material for visual change is small white stucco chips.Larger stuff does not bind as well as the small stones.

 

[beryl10]

Thanks for all the replies.

Mike Halloran: About the cement dusting, I wonder if you could post, or send me a picture of this. Is it a solid layer of cement, or just a light dusting that gives the appearance of a wash? Does it look like cement, or more gray, like weathered asphalt? And, what is the final color? Did you do this on top of the brand new asphalt while it was still tacky?

And, about the gravel compacted into asphalt. Is this usually done on the typical densely graded 1/4 inch wearing course or a more open graded asphalt? How small should the chip be? Francesca: do you know what the red chip is that is used on London streets? Its a very intriguing technique. The addition of some colored aggregate would add alot of visual texture to an asphalt driveway.

 

[francesca]

Sorry, I don't know any more than I've already said... but I did find this, which might be useful.

 

[MikeHalloran]

My neighbors did it, >45 years ago, two light dustings on fresh asphalt. It took the color of cement and the texture of asphalt. It didn't look like concrete, and it didn't look like asphalt. Imagine weathered asphalt with a gray-white matrix. Sort of like asphalt weathers here in SoFla, but lighter. I can't say that I cared much for the color.



Mike Halloran
Pembroke Pines, FL, USA

 

[BigH]

The highways maintenance site (as directed by francesca's "this" is a damn good one. Lots of really good basic material on the site. Well worth a visit.