I could feel the heat coming off it when I stood next to the repaved section. They didn't repave the parking area at the edge. Opened to traffic again, seems firm enough to drive on at 160⁰F.
this post was submitted on 06 May 2026
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Hmm, that's interesting. Don't you guys generally use concrete for paving in the US? In building construction, you're supposed to give concrete like a month to fully harden, even though it already looks firm after a day or so.
For paving, they're likely using a hardening accelerator, so the timelines wouldn't be the same, but if building construction is anything to go by, it seems like you'd want to give it as much time as possible, not send cars on there while it's still hot. 🥴
Even with accelerators it still needs a few days (usually about a week) to harden to 80% strength, and it will never be quite as strong as it would be without an accelerator.
I think that’s part of the reason we don’t use concrete pavement more often. It certainly lasts a lot longer, but laying it is way more time consuming. Asphalt is ready to go within a day, just needs to cool off.
Generally? I don't think so. I think concrete gets used in heavy intersections, super busy streets, and some parts of highways/freeways, but not for all the branching streets. Smaller/less used roads and residential are generally pavement/asphalt. Though some HOAs like to use concrete for the longer expected lifespan and then don't budget for repairs so it turns to crap after a while. That said, I'm not a professional, I just live here. Not in an HOA, thankfully, but near one with terrible concrete roads.
Its uncommon to see concrete roads in the US but there are a few of them around. That being said it could be more common in some states than others.
Arent the majority of your freeways concrete?
Structure is concrete, road surface is asphalt.
For all freeways are all asphalt? Thats not correct Cali for a start has been moving to concrete.
Concrete is used for the top layer for higher load areas were budget and the foundations can support it as its more inflexible. Asphalt is used as its cheaper (initially, it will need renewing more often) and it will support more movement for the foundations and worse weather.
We (UK) had part of the M25 done in the same style, but it was shit as we cut the budget and its lots of small joined sections due to complexities of using larger slabs. The foundation has since moved about and the gaps get bigger.