Pavement expands and contracts during extreme hot and cold spells. This allows water to get under the pavement and leads to potholes.
The City of Columbia Street Division is now piloting an Asphalt Recycler to make a hot mix for repairing potholes on city streets even on cold days. A Hotbox trailer is then used to transport the hot mix to the street while keeping it a steamy 350 degrees.
Cold mix patching is still used as needed because the preparation process is shorter. In the long run, though, the hot mix patching reduces the cost of pothole repair by up to 40 percent because the patch is more durable and the patching material is less expensive.
Report a Pothole
Hot Mix Process
Here’s how the pothole repair process works.
1 A loader pours crushed asphalt into the Asphalt Recycler, which
heats and churns it to create the “hot mix.”
2 The loader takes the hotmix from the recycler …
3 … and dumps it into a mobile Hotbox that keeps the asphalt
at 350 degrees throughout the pothole patching process.
(The hot box has a heating element that runs on propane.)
4 Crews pull the Hotbox throughout the city, patching potholes
with steaming hot mix as they go. Once a pothole has been spotted or reported, it’s the goal of Public Works to repair it as soon as possible (preferably within 24 hours), weather and resources permitting.
“How Potholes Form“ – USA Today