Road Construction

[CtrlAltDel]

They are currently repaving the street outside my apartment, and aside from the annoyance, it's quite interesting. It's something really to see these giant machines and what they're capable of.

Yesterday, they ground up the old asphalt pavement (which wasn't in bad condition, but whatever) with something that seemed similar to a giant planing machine for wood attached somehow to a long conveyor belt that lifted the ground up asphalt off the ground and into a truck. This truck had to stay under the conveyor belt or some of the ground up asphalt would fall to the ground, which some did. I don't know how the remaining bits of asphalt got picked up, since I had to do some work, but by the time they were done, there were no stray pebbles.

Today, they are laying down the new asphalt, and I think they're going to do it in two layers. There's a machine that lays down a strip of asphalt about 10 feet wide, and then it gets run over by a steamroller. The process is interesting, since I'm at the end of a cul-de-sac, so they've had to deal with the bulb out. What they've done is have the first strip they laid follow the curb, with the inside strips being parallel to the street.

I can't imagine that any of this is news to too many people here, but it is fascinating to see these things in action, which of course, is no small part of why I enjoy this hobby.


Not that it's too terribly important, but the machines they are using are a:
Caterpillar AP1055F
Hamm HD 120i
Hamm GRW 180i

[Big John]

First was the process of removing the asphalt for recycling.

The 2 layers of new asphalt is the lower binder course, then a liquid binder is sprayed on, then the upper riding surface.

[triplemultiplex]

I don't know how the remaining bits of asphalt got picked up, since I had to do some work, but by the time they were done, there were no stray pebbles.

There's usually a machine w a sweeper attachment to wrangle the bits that weren't scooped up by the milling machine.  Sweep the chunks into the bucket of a front-end loader or similar so they can add them to a dump truck.

Those dump trucks are taking that milled asphalt to wherever they are mixing new asphalt for the project and they incorporate much of that material into the new hot mix along with fresh ingredients.  Who knows, maybe some of the same pieces of aggregate found their way back to the same cul du sac.

[jeffandnicole]

If the old asphalt appeared in good condition, then they're doing it right. Chances are it was in ok condition, but close to a failing point, or it was just due to be replaced on a set schedule.

All too often I see the following two complaints:
  Why are they repaving the road? Everything is fine.
  Why aren't they repaving the road? It's a disaster.

Transportation department work is tough when the public thinks they are always doing it wrong.

[GaryV]

All too often I see the following two complaints:
  Why are they repaving the road? Everything is fine.
  Why aren't they repaving the road? It's a disaster.

Transportation department work is tough when the public thinks they are always doing it wrong.

You forgot, "Why are they working on this road?  The next one over is much worse."

[CtrlAltDel]

I don't know how the remaining bits of asphalt got picked up, since I had to do some work, but by the time they were done, there were no stray pebbles.

There's usually a machine w a sweeper attachment to wrangle the bits that weren't scooped up by the milling machine.  Sweep the chunks into the bucket of a front-end loader or similar so they can add them to a dump truck.

Is it kind of like a street sweeper or something else? What I'm imagining is pretty much a giant vacuum cleaner.

Those dump trucks are taking that milled asphalt to wherever they are mixing new asphalt for the project and they incorporate much of that material into the new hot mix along with fresh ingredients.  Who knows, maybe some of the same pieces of aggregate found their way back to the same cul du sac.

Is the turnover really that fast? They scraped the old asphalt on Wednesday and repaved on Thursday. I was imagining more of a headache involved with the process, but it was over and done with pretty quick.

All too often I see the following two complaints:
  Why are they repaving the road? Everything is fine.
  Why aren't they repaving the road? It's a disaster.

Transportation department work is tough when the public thinks they are always doing it wrong.

You forgot, "Why are they working on this road?  The next one over is much worse."

That was pretty much my thought, to be honest. My place is located near the border between two different towns, and the one I live in definitely seems more proactive about street paving. Once you cross into the other town, the streets are potholed and cracked. They've covered some of them in chip seal, and it's not especially new chip seal, either.

[triplemultiplex]

I don't know how the remaining bits of asphalt got picked up, since I had to do some work, but by the time they were done, there were no stray pebbles.

There's usually a machine w a sweeper attachment to wrangle the bits that weren't scooped up by the milling machine.  Sweep the chunks into the bucket of a front-end loader or similar so they can add them to a dump truck.

Is it kind of like a street sweeper or something else? What I'm imagining is pretty much a giant vacuum cleaner.

It can be identical to the street sweeper you might see DPW using around town.  Or maybe an attachment on a skid steer loader or similar:


Some companies will have a dedicated machine for this task.  Example:

Those dump trucks are taking that milled asphalt to wherever they are mixing new asphalt for the project and they incorporate much of that material into the new hot mix along with fresh ingredients.  Who knows, maybe some of the same pieces of aggregate found their way back to the same cul du sac.

Is the turnover really that fast? They scraped the old asphalt on Wednesday and repaved on Thursday. I was imagining more of a headache involved with the process, but it was over and done with pretty quick.

It very well could be.  Or the old, milled asphalt could sit in a pile for days or weeks before it gets mixed into to new hot mix for another project.

[CtrlAltDel]

It very well could be.  Or the old, milled asphalt could sit in a pile for days or weeks before it gets mixed into to new hot mix for another project.

That's much faster than I would have thought. Color me impressed.