by Dan Chambers on Wed Jan 05, 2011 9:22 pm
pecivil wrote:wow if we have expansive clayey soil we are hosed.
On cold patch, I can only say fixing potholes is one of the most vexing problems in civil engineering. For the last 100 years people have been trying to come up with a way to do that, and there ain't one yet that is truly permanent. If there was a way the inventor would be a bazillionaire. Just take a look at the concrete patches there now and they are only a year or 2 old? And that is on a parking lot that has a low traffic volume at (autocrosses notwithstanding) at very low speeds. You can never get a good enough bond betwen old and new, and every tire that runs over it works that joint over and over until it fails again. The only real fix is to demo and repave. Just saying.

All true. And ... cold-patch tends to expand and contract along with the surrounding asphalt material, making for a more uniform surface morphology. Whereas concrete is, well ... concreted in place and not as pliable as its surrounding asphalt bretheren when heated and cooled. Addtionally, cold-patch has an amount of bitchumen (the same basic agent as hot-batch asphalt) that conctrete lacks, so cold-patch is more likely to bond to like material than cementing agents that repel bitchumen. And ... asphalt has an inherent ability to flex under load as it is in fact a constantly hardening material (like the resin on a surfboard, or the glass [aka viscous silica] in your house windows). Concrete is as hard as a rock once the cementing agents chemically go off.
FWIW

Dan Chambers"It's
just a "well prepared" street car ... or a very, very well-mannered track car."

1983 SC #91 3.6L, "Black Pearl" Livery
1987 944 (gone but not forgotten)