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How good are American roads?

(www.construction-physics.com)
193 points chmaynard | 2 comments | | HN request time: 0s | source
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rconti ◴[] No.42196461[source]
> Interestingly, in all cases urban roads are worse quality than rural roads, presumably because they see higher traffic than rural roads.

There's more infrastructure under urban roads. Crews come in to fix some utility, shred a section of a lane, patch it poorly with dissimilar materials, and leave.

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vel0city ◴[] No.42196736[source]
You're probably also going to have far fewer massive vehicles on those rural roads. More things like pickups yes, but probably considerably fewer semi-teicks and busses and fire trucks and cement mixers what not. Those big trucks passing through are going to stick to interstates far more often when going through rural areas.
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FuriouslyAdrift ◴[] No.42196979[source]
City buses are what really shred urban roads (and winter plows)

https://www.kgw.com/article/news/verify/yes-bus-more-road-da...

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PaulDavisThe1st ◴[] No.42197198[source]
In the mid-90s, Seattle started excavating its bus-stops-on-a-slope and pouring a new concrete foundation, because the busses were warping the asphalt so badly.

I was just back there this last weekend, and you can no longer see any of the concrete - it has all been coated with asphalt. However, I assume its a rather thin layer because none of the bus stops I checked show the signs of damage that were becoming common in 90-96.

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teh_klev ◴[] No.42197925[source]
I did google "bus-stops-on-a-slope", but nothing jumped out. What are "bus-stops-on-a-slope"?
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1. stonemetal12 ◴[] No.42198626[source]
Asphalt, like glass, is an amorphous solid. When a heavy truck sits still on asphalt, asphalt will flow out from under the tires. Not only do you get a depression and eventually a pot hole where the tire was, and you get a little hill next to it.

You just about need an offroad vehicle to avoid hitting the street.

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2. PaulDavisThe1st ◴[] No.42198885[source]
Moreover, when a heavy vehicle like a loaded passenger bus has to accelerate from stationary on a hill, it exerts incredible force on the asphalt below it.