Originally Posted by Wyofire
At least one of my routs has been hosed for a while by the city, and it looks like at lest a portion of all of them will be. Rather than repaving streets as they get in bad shape our town goes through every couple years and "chip seals" all the streets in town, and I have to ride at least a portion of the redone area. For those who aren't familiar with this stuff, they spray down thin layer of hot tar, and then put a layer of chipped rock over it. Rather than rolling the surface and sweeping away the excess rock they just wait for the normal traffic to press in the rock, and then just let the traffic and weather push the excess out of the traffic lanes. Basicaly the stuff will shred a set of tires in short order, and makes the rough fairly rough for a couple months. Once everything gets pounded in it's not bad, but then they'll seal it again.
Around here, there were experiments with chip seal in the 1970's, but they pretty much gave up on it, what they found gave the smoothest, cheapest and most durable surface was to, recycle the asphalt. They start by looking at the sidewalks and curbs, any damaged sections are replaced, old sidewalks that do not have wheelchair ramps, have them installed. This often means that the edge of the road may need to be repaired after the curbs are done. They grind off the surface of the road, removing 2-5cm of the surface, this material goes to the asphalt recycling plant, where the material is sorted and the non-asphalt materials are removed, the asphalt material is then heated to cause the tar to melt, this material is then mixed with additional material to form new asphalt. They add a layer of fresh asphalt to the road, they paint on new lines, and it's good for about 10-15 years. By doing this, they find that a road bed will last 80-100 years, at which point, underground utilities which are often below the road, like sewer and water lines, probably also need replacement, so they can do everything at once.
What bugs me sometimes, is that a developer is building a house beside the road, the city doesn't force them, to do road work before they resurface the road, so they resurface it, and then the developer digs it up a week later to do their work, and you end up with a bump in the new road.
One of the advantages to resurfacing is that when they resurface a road, they can bring it up to current standards, for example if a road did not have sidewalks, they will install at least one sidewalk, since the current standard is to have at least one sidewalk on low traffic streets, and two on higher traffic streets. This also means that no road is more then 15 years behind the current standard. Eventually they will add bike lanes to the standard as well, as more and more people switch from cars to bicycles and scooters.
They do go over the roads once a year, and any cracks are usually filled in with tar, which is covered with stone dust to keep tires from sticking to it, you have to be careful on the tar though, it can be very slippery, especially if it gets wet, it's easy enough to see though, but often you get a strip of it, right where bicycle tires seem to go......