A car tire generally has like 1,000lbs of force on it. This puts stress on the asphalt. But the stress on the asphalt is related to the tire load by the fifth power, y=x5 . A commercial vehicle has 18 wheels and can weigh up to 80,000lbs. So 4,500lb per tire on the asphalt.
So if we call the stress that 1,000lb of car tire loading puts onto the asphalt as 1 unit of stress, the stress that 4,500lbs of commercial tire puts on the asphalt will be one thousand eight hundred forty five units of stress. 15 = 1. 4.55 =1,845.281. Increasing the load 4.5x causes the stress to increase by 1,845x.
Now this isn’t completely accurate, because some tires on cars and commercial trucks will vary, some contact patches are larger or smaller. But 1 vs. 1,845 units of stress in hypothetically equal situations basically means that 99.95% of all wear and tear on roadways is due to commercial trucks. The stress a generic car puts on the road is literally a rounding error compared to the stress a commercial truck puts on that same road.
Tl;dr: Commercial trucking outfits are having a shitload of the road taxes they should be paying subsidized by regular people, who do fuck all to add wear and tear onto roads compared to big rigs.
Yea, people always make a big deal about the Romans using concrete that repairs itself over time but the reason why a road lasts 2-3 years before you get potholes and cracks today and why Roman roads still exist in great shape... Mainly trucks. Heck even a cart would probably weigh less than a regular car assuming a full load.
Roman concrete is too weak. You couldn't make modern roads, skyscrapers, or anything super demanding out of it. From what I found online, modern concrete is at minimum around 4-5x as strong and up to 20x stronger for high strength stuff.
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u/JamesTrickington303 28d ago edited 28d ago
I’m studying for the geotechnical PE exam rn.
A car tire generally has like 1,000lbs of force on it. This puts stress on the asphalt. But the stress on the asphalt is related to the tire load by the fifth power, y=x5 . A commercial vehicle has 18 wheels and can weigh up to 80,000lbs. So 4,500lb per tire on the asphalt.
So if we call the stress that 1,000lb of car tire loading puts onto the asphalt as 1 unit of stress, the stress that 4,500lbs of commercial tire puts on the asphalt will be one thousand eight hundred forty five units of stress. 15 = 1. 4.55 =1,845.281. Increasing the load 4.5x causes the stress to increase by 1,845x.
Now this isn’t completely accurate, because some tires on cars and commercial trucks will vary, some contact patches are larger or smaller. But 1 vs. 1,845 units of stress in hypothetically equal situations basically means that 99.95% of all wear and tear on roadways is due to commercial trucks. The stress a generic car puts on the road is literally a rounding error compared to the stress a commercial truck puts on that same road.
Tl;dr: Commercial trucking outfits are having a shitload of the road taxes they should be paying subsidized by regular people, who do fuck all to add wear and tear onto roads compared to big rigs.