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I cannot believe a studded shoe would have any impact whatsoever on a concrete pavement. Human weight is nothing compared to that of a car.

labawi 2300 days ago

Weight of a masonry hammer is nothing compared to the weight of a human, yet it can destroy concrete with ease.

I'd guess it depends on how and how much you walk on what kind of pavement with what kind of studded shoes. Damage can realistically be imperceptible or ugly.

runarberg 2300 days ago

There are a lot more cars, running on much greater speed, for a lot longer distance, with much greater weight, then humans walking on spiked shoes.

The masonry hammer runs on much greater speed, with much more force, a lot more often then the human steps on the peace of concrete being taken apart.

fiblye 2300 days ago

Concrete sidewalks are pretty fragile. Unless they're freshly laid, most that I see have cracks and pits to some extent (probably mostly attributable to cooling/heating and water). Some people also seriously drop their feet down hard when they walk, and if they've got little bits of metal sticking out from the bottom of their shoes, I imagine that damage adds up and doubly so if it slams down an existing crack.

The ground pressure of a human wearing studded shoes is an order of magnitude or more higher than the ground pressure of a car.

The ground pressure of a car is exactly equal to the PSI that you inflate the tire.

Take the weight of a human and divide by the surface area of of a started shoe you will find a significantly higher number.

>>The ground pressure of a car is exactly equal to the PSI that you inflate the tire

Wait, what? So if the tire is flat, the car exerts no pressure on the ground? :-P

I know you are joking but just to answer the question anyway, if the tires are completely flat then they are not supporting the car and you can't use them for measurement.

If the tires are partially flat then they are supporting the car and the PSI is correct and you'll notice the tire spreads out wider on the road so the ground force is lower because it's spread out over a larger area.

Technically you have to also include the springiness of the sidewall in the measurement not just the PSI of the air.

>>if the tires are completely flat then they are not supporting the car and you can't use them for measurement.

Run-flat tires are a thing though - you can drive on them even with no internal pressure, there can be a gaping hole in it and you can still drive on them. So what's the pressure the car exerts on the road when driving then?

samatman 2300 days ago

A hint: the area of the tyre in contact with the road is in square meters, and the mass is in kilograms.

You'll find that, if you multiply the force of gravity by the mass, and divide by square meters, you'll have Pascals.

And there's your answer.

That's where the "springiness of the sidewall" I mentioned comes in.

Normally (with inflated tires) it doesn't play much part. But with flat tires it can come to dominate.

mirimir 2300 days ago

I've done that. They catch fire, after a while.

chillwaves 2300 days ago

I can understand the car part (pounds per square inch) but why would a person's feet have more than 35 psi? If I have something like 60 (30 per) square inches of feet, and I weigh 180lbs, would that be 3 psi for my feet? Even if only parts of my feet were striking the ground at a time, how would that be more than a car?

High heels. Also in this specific case we are talking about metal spiked ice shoes.

chillwaves 2300 days ago

Thanks, that makes it very clear.

All your posts are helpful.

For example, I never before considered the implications of tire PSI.

Fjolsvith 2300 days ago

By your logic, water running across concrete wouldn't create any wear on the concrete, but in truth, it does.

Yeah, but there's a lot of water, and it can run over concrete for hours if not days at a time - of course it has an impact simply due to the sheer volume of it. Again, how does it compare to the miniscule impact of studded shoes?