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Pollution from tire wear is worse than exhaust emissions?

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Re: Pollution from tire wear is worse than exhaust emissions?

#271

Post by ars »

gambiting wrote: post #260
ars wrote: post #255

Earlier quoted context omitted.

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 i…

>>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?

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.

Re: Pollution from tire wear is worse than exhaust emissions?

#273

Post by samatman »

gambiting wrote: post #260
ars wrote: post #255

Earlier quoted context omitted.

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 i…

>>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?

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.

Re: Pollution from tire wear is worse than exhaust emissions?

#274

Post by a3n »

jessaustin wrote: post #203
masklinn wrote: post #179

Earlier quoted context omitted.

> Truck driver. Not quibbling, just adding nuance. You're absolutely quibbling though. > So you should include in your calculations that the load is spread out over eighteen tires, as above. The fourth power rule is specifically about axle load, not about wheel load. It's also an estimate / rule of thumb (which is why it's so useful), not a precision instrument. But hey if you want more precision than the FPR we can…

Yeah, they use dual tires so that they don't pop catastrophically, not to spare the road from wear.

That's been the benefit to me, still having a drivable rig when a tire shreds.

But, there is also something called a "super single" that's a double wide single wheel/tire, with one on the end of an axle rather than two. I'm told they're cheaper and lighter total, as opposed to the more common two per end. I've pulled a few trailers that had them. I don't really know why one or the other, I just drive them.

Re: Pollution from tire wear is worse than exhaust emissions?

#275

Post by a3n »

masklinn wrote: post #179
a3n wrote: post #63

Earlier quoted context omitted.

> Take a 40t truck with 5 axles vs. a small car with a weight of 1t and two axles ... Truck driver. Not quibbling, just adding nuance. For your typical 40t scenario, allowed max weights are: 12,00 pounds on the front steering axle. It has one tire at each end. 34,000 pounds total on the two tandem "drive" axles on the truck. There are two tires at the end of each axle, so four per axle, eight total at the drive axles…

> Truck driver. Not quibbling, just adding nuance. You're absolutely quibbling though. > So you should include in your calculations that the load is spread out over eighteen tires, as above. The fourth power rule is specifically about axle load, not about wheel load. It's also an estimate / rule of thumb (which is why it's so useful), not a precision instrument. But hey if you want more precision than the FPR we can…

> The fourth power rule is specifically about axle load, not about wheel load.

Misunderstood that, sorry.

Re: Pollution from tire wear is worse than exhaust emissions?

#276

Post by Karrot_Kream »

pmiller2 wrote: post #214
dragontamer wrote: post #125

Earlier quoted context omitted.

Not quite IMO. Anyone who has done any amount of virtual traffic engineering (aka: Factorio, City Skylines, OpenTTD) knows that intersections are where the bottlenecks are. Its incredibly difficult to design a max-throughput intersection. Roads have a huge amount of throughput, most "traffic" just gets stuck at offramps and traffic lights. Narrowing a road to make room for bike lanes is a lower cost than people might…

It’s not all about throughput. Taking away car lanes in favor of bike lanes usually takes away parking as well. While that certainly has the desired effect of reducing car traffic to the area, it also increases the difficulty and expense of travel to the area. We’re seeing this in Oakland now, where they’re putting in bike lanes and taking away parking, while simultaneously doing nothing about the limited public tran…

I mean, or you can ride a bike in these new bike lanes in one of the flattest and temperate climates in the US?

Oakland is littered with cars along roads in every neighborhood you go on, and the police barely enforce anything resembling traffic code (due partially to complicated historical reasons). In some neighborhoods, I've seen duplexes with more land area in cars than living space (so is it a wonder that poorer people here live in their cars when it's so easy to own and park a car?)

A bike lane or two makes it cheaper for most folks (yes including the folks living in the pop-up Oakland housing shelters, they own a lot of bikes) to safely move around, and reduces traffic from our generally saturated roads. Given the limited paving budget here (and how tectonically active the hills are), it's a wonder that bike infra has taken so long.

Moreover, the heavy private vehicular traffic in the area makes it very difficult for buses to navigate their routes in a timely manner, and taking parking off the road for bike lanes and BRT is a much cheaper way of enabling transit in the area that laying down rail.

Re: Pollution from tire wear is worse than exhaust emissions?

#277

Post by wool_gather »

npunt wrote: post #201
ratel wrote: post #164

Hold on: The claim is this: > "Using a popular family hatchback running on brand new, correctly inflated tyres, we found that the car emitted 5.8 grams per kilometer of particles." It does not seem to be a mistake: > "Compared with regulated exhaust emission limits of 4.5 milligrams per kilometer, the completely unregulated tyre wear emission is higher by a factor of over 1,000." A tire might way up to 15 kilograms f…

Excellent use of back of the envelope math. I wonder if maybe the loss is non-linear, and a bit more is coming off because the tires are brand new. Perhaps there’s some coating on new tires before they ‘break in’?

Perhaps, but that would have to be a pretty steep curve, and one would expect that kind of falloff to have shown up in the data here (unless they literally drove the car once for only 1km, which...would be its own problem for credibility).

Re: Pollution from tire wear is worse than exhaust emissions?

#278

Post by toss1 »

labawi wrote: post #202
toss1 wrote: post #165

Earlier quoted context omitted.

Exactly. Question is, what is the dosing level that would cause harm, and what are the routes that this material takes that might rise to such a level, vs how much is, e.g., stuck on the pavement and washed into the ditch with every rain?

> stuck on the pavement and washed into the ditch with every rain? This is also an important problem - there is a lot of synthetic rubber particulate in waterways and oceans - a notable fraction of all microplastics.

Exactly, so while the authors are ringing alarms about the particles from a health POV, they might be a irrelevant to that threat, but a major threat to certain ecosystems, or nothing at all.

Certainly bears good investigation, but far too soon for conclusions (an I'm usually biased towards acting based on Precautionary Principle, but this just seems far too indirect to even make assumptions, let alone conclusions).

Re: Pollution from tire wear is worse than exhaust emissions?

#279

Post by cptskippy »

cma wrote: post #229
cptskippy wrote: post #184

Earlier quoted context omitted.

Interior dimensions are all very similar. Exterior, the Model S is the largest, followed by the Camry, Model 3 then distantly the Corolla. Shldr Hip Head Leg Model S: 57.7 55.0 38.8 42.7 Camry: 57.7 55.4 37.5 42.1 Model 3: 56.3 53.4 40.3 42.7 Corolla: 54.0 53.9 38.0 42.0 WB Len Wdth Hght Model S: 116.5 196.0 77.3 56.5 Camry: 111.2 192.7 72.4 56.9 Model 3: 113.2 184.8 72.8 56.8 Corolla: 106.3 182.5 70.1 56.5

Interior volume of Camry is 115 cu ft (27lbs per interior cubic foot without gas, some marginal amount more with the same amount of gas as P90D's range, which only takes around 60-80lbs of gas or so). Model S P90D is 120 cu ft (41lbs per interior cubic foot).

Does that take into account cargo space?

Re: Pollution from tire wear is worse than exhaust emissions?

#280

Post by sjg007 »

londons_explore wrote: post #182
superpermutat0r wrote: post #174

I live next to a very busy road (6-lane). When I moved in, the closets were filled with black stains. My brother-in-law cleaned it and said he never saw that kind of dirt. The closets are dirty again. As time passed I also never encountered that amount of dust. The dust was also extremely different from the dust when I lived in the forest, dark colored and plentiful. It accumulates very quickly, it gets abandoned-hou…

If you have a central air heating system like most houses do, you should add a filter near the fan. You won't catch all the dust, but you'll collect a lot of it, making your air healthier to live in

I would run a couple standalone couple hepa aircleaners as well.
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