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> The damages are proportional to the root of the weight

No, road damage is proportional to the 4th power of axle weight. So a car that's 50% heavier will do 5x the damage to the road. (Assuming the same number of axles.)

That's an interesting formula - why is it the 4th power of the axle weight?

It's an empirical result, derived from some testing by the US government in the 1950s [1].

[1]: https://en.wikipedia.org/wiki/Fourth_power_law

How does one get a four in an exponent here? Is there a link to the math?

Edit : cool link below, but includes the disclaimer

“The accuracy of the law of the fourth power is disputed among experts, since the test results depend on many other factors, such as climatic conditions, in addition to the factors mentioned above.”

But 5x a very small number is still small.

Loaded semis weigh 20-40x a car. That's 160,000x the damage.

And as the author points out - it's not going to change much whether the semi is gas or electric.

It's the load of the truck that matters.

Loaded semis also have far more axels, so your math is just wrong out the gate.

Another factor that I haven't seen addressed is that Passenger vehicles are much more apt to dive on the brakes to stop. My observation is that roads fail first where people are slamming on the brakes.

Max load for trucks in Europe is usually 10 tons per axle. No passenger vehicle comes even near that.

> My observation is that roads fail first where people are slamming on the brakes.

It's possible you're getting deceived here, because the highest wear road surfaces are made from more durable material, and areas where drivers might need to slam on the brakes often have high friction surfaces, which are more wear-prone.

So the industrial area where dozens of fully laden 18-wheelers are making sharp turns every day gets paved in the most durable concrete mix possible, the school zone pedestrian crossing approach gets a high-grip sandpaper-like surface, and a few months later it looks like the school zone is getting a lot more wear.

Highly unlikely given that the observation is relative to the roads in the immediate vicinity. This is very observable on flat off-ramps. the last ~200 feet before the stop at the end of the off ramp will get ruts within a year or two, but the rest of the off ramp is fine and the other side of the road where cars are accelerating is just fine.

> Norway, sitting on gigantic oil reserves

The US is currently producing more oil than any country at any time in history. [1].

Also the US has much, much larger reserves than Norway [2] Norway has 0.31% of the world's oil, the US has 2.1%

So I'm not sure why Norway's oil has anything to do with this discussion.

[1] https://www.cnn.com/2023/12/19/business/us-production-oil-re...

[2] https://www.worldometers.info/oil/oil-reserves-by-country/

That's 10x more oil per capital in Norway.

And the US is producing more than any other country at any other time in history....

Mind that Norway is a lot smaller, only 5.5M inhabitants, thus per capita the oil revenue is a lot higher. Also in Norway less of the money is going to few private corporations, but to the state, which invests large parts into profitable pension funds, which gives Norway stellar financials and the ability to invest and subsidize into whatever future endeavors they see, like transition to EVs, as they see that oil supplies will tighten up.

So the argument isn't that Norway is rapidly adopting evs because they have large oil reserves, the argument is that Norway is adopting evs because they setup their oil reserves so the profits benefit everyone and not just big corporations.

Quick! do education and healthcare next!

prev?

> Also in Norway less of the money is going to few private corporations, but to the state, which invests large parts into profitable pension funds,

If only other oil-producing countries had the ability to exploit their oil reserves for their own benefit instead of just giving it away to a few private corporations...

Crazy stuff, I know.

> The damages are proportional to the root of the weight

I'm not sure where the root of weight estimate came from, because you seem to understand the overall effect of weight reasonably well.

In any event, road damage is roughly proportional to the fourth power (not square root) of axle weight (and linear with axle count).

Lots of American Exceptionalism in this comment and the replies.

The Norwegian state makes so much money off of oil because of how well they manage the revenues. The US could do the same thing but chooses not to.

The difference between the US and Norway isn’t in the amount of fossil fuel reserves one possesses vs the other. It is in how the money from those resources is used. The US privatizes it while Norway puts it towards the public good.

Their oil per citizen is not equivalent. Norway is producing 0.38 barrels of oil per day per citizen, while US is 0.034. That's over an order of magnitude difference. Could the US do better? Yes. Is Norway well run and has an abnormally high amount of oil per citizen? Yes of course. Yet your claim is still mostly false if US was run just as well.

> Could the US do better? Yes.

That is like comparing a toddler to Usain Bolt in a race and saying the toddler could have done better.

The US isn’t even trying to manage any money from its resources in a way that benefits its citizens in the long term. Americans should be furious about how poorly managed the wealth from these natural resources is being managed, but instead seem to think that America is too different from Norway to even consider doing a similar sovereign wealth fund. The same bad arguments get made about healthcare all the time.

> The US isn’t even trying to manage any money from its resources in a way that benefits its citizens in the long term

Different goals. Gas is and has always been (afaik) cheaper for American citizens than for Norwegians. Having more money in your pocket is a long term benefit for Americans.

> Ah yup... Norway, sitting on gigantic oil reserves.

If only the US had oil. I can't imagine what we could do if we produced 5x the oil that Norway does.

Still be 12x in arrears?

You know what’s common for metro Hamburg and Norway? Each has a population of 5.4 million.

You know what’s not common? Hamburg doesn’t sit on massive natgas and oil reserves.

I don't think we (Norway) should be a poster child for EVs. Or, we've done great in increasing their share, but at what cost? Changing cars from ICE to EVs doesn't really solve most of the problems cars pose to our society. The money poured into this each year could've built so many new railways, metros, supported public transport for decades etc.

https://www.vox.com/future-perfect/23939076/norway-electric-...

> But citing Norway as some kind of EV posterchild is quite hilarious when it's their oil business subsidizing EVs.

It's even more hilarious when you compare the population count.

The population count is an argument that puts the US in a further negative light: They stand to gain significantly more due to how economies of scale work than a country with only 5 million people does.

> Besides that the "heavier = bad for the road" (which TFA hints at) is pure non-sense: a regular car or a car twice the weight of the regular car will do exactly jack shit to damage the road.

This is not bullshit. Road damage scales as the _fourth_ power of the axle weight. BTW, that's also why buses and heavy tracks are so damaging. One bus does can easily do the same damage as several thousand cars.

Wiki: https://en.wikipedia.org/wiki/Fourth_power_law

I think that's why EVs don't really affect the road. You could double the weight of every car in the country, and it would increase road wear by like 3% because of how ridiculously disproportionately large vehicles cause it.

lmao

Norway is deservedly the "poster child "because 90% of their sales are BEV, buddy.

And it's not a ludicrous amount of money that can only be funded by oil sales that is being spent on EVs. It's a drop in the bucket compared to US expenditure on auto infrastructure.