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Comment by PaulDavisThe1st | Hacker News Reader

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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They opened a new truck stop near me with asphalt roads. 6 months later they tore it up for concrete because the asphalt shifted into lumps where the trucks were turning cono

I did google "bus-stops-on-a-slope", but nothing jumped out. What are "bus-stops-on-a-slope"?

I think they meant that the bus stop is on a hill maybe?

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.

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.

Doesn’t just happen on hills you can see this phenomenom on flat intersections too that have seen a lot of nearby construction vehicles (cement trucks, dump trucks, etc are probably the worst).

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