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By your own explanation, it should cost maximum $600,000, especially since a well trained crew could leverage their skill at scale. But this even seems like a l

By your own explanation, it should cost maximum $600,000, especially since a well trained crew could leverage their skill at scale. But this even seems like a lot to me: $60k is an enormous sum to pave 20 feet of driveway. I was looking at having it done and it was closer to $6k so it should be even less to pave 4 blocks. This issue, to me, is hugely concerning. Why did one mile of the bay bridge cost as much to build as funding NASA for 6 years?

HCIdivision17 10y ago
Oh no, my estimates were really in favor of the parent's comparison. That $600k is a lowest-bidder minimum, expecting to redo in a month when it fails. I'd be interested to know more about the breakdown, and I'd bet at least some municipalities are required to share it. A well trained road crew is likely pretty expensive, and as others noted, there's a lot more to a road than a driveway. Most driveways I've seen are largely cement planks, whereas a road is layers of differing materials to ensure frequent use doesn't destroy it too quickly. As for bridges. Eugh. I dunno. Those things are often crazy expensive. I wouldn't be surprised though, since that bridge is rather large and suffers a lot more wear and tear than NASA. I mean, they just need to punch a few one-time use rockets into space, but that bridge has to deal with thousands of semis. Space is a nasty place, but I'm betting thousands of trucks barreling over is harder to deal with year in and out.
Vraxx 10y ago
Just going off of the comment you're responding too, that $600,000 corresponds to one block when the original example specified 4 blocks for $1.5 mil. I don't claim to know anything about street paving economics, I just wanted to point out the disconnect.
zrail 10y ago
The load and traffic that a typical driveway sees is far less than what a city block would be expected to see. There's more concrete, rebar, gravel, etc for every square foot of surface. Interstate-grade highways have 8-10 inches of reinforced concrete. Driveways are typically 4 inches and are not reinforced. The same goes for asphalt, if that's what they're using. It'll be cheaper because it's not designed to last as long, but the scaling factors hold.
VLM 10y ago
Heaviest current production SUV is 6274 pounds for a Lincoln Navigator https://en.wikipedia.org/wiki/List_of_automotive_superlatives#Curb_Weight https://en.wikipedia.org/wiki/List_of_automotive_superlative... Federal interstate MINIMUM construction standard is to assume 105500 pound semi trucks. https://en.wikipedia.org/wiki/Federal_Bridge_Gross_Weight_Formula https://en.wikipedia.org/wiki/Federal_Bridge_Gross_Weight_Fo... IF you could get the big trucks off the roads, maybe use very small pickup sized autonomous self driving trucks running on and 3 inch thick concrete like a driveway, THEN $600K would probably be achievable. There are also correction factors that a SUV probably never exceeds 5 MPH on a driveway and usually doesn't park there and frankly most cheap driveways would be destroyed by a vehicle that heavy anyway, whereas the road has to survive 24x7 service at 75 MPH. The pounding the road takes at 75 MPH at 105500 pounds must simply be incredible.
- HCIdivision17 10y ago
  Fun trivia: road damage follows a fourth power law. [0] Double the weight and you do sixteen times the damage. [0] Link to link: http://www.vabike.org/vehicle-weight-and-road-damage/ http://www.vabike.org/vehicle-weight-and-road-damage/
ska 10y ago
Why would you assume that the paving on your driveway is fit for purpose on a public roadway? At the very minimum, load and wear patterns are vastly different. Drainage probably looks quite different also. I wouldn't be surprised if it requires a fundamentally different approach. Would you?
- dclowd9901 10y ago
  All I'm assuming is that building a road is a highly scalable operation, and it seems evidence backs that assumption up. There are an incredible amount of machines that are highly specialized in laying roads down. Does it require more than a residential driveway? Yes, ok. But why does it seem like costs rise exponentially with project size rather than logarithmically?
  - ska 10y ago
    I'm more questioning whether your home driveway is in any way useful as a base cost estimate. I don't know either. But if it turns out that paving your driveway to the same standard would cost $100,000 the scaling looks much better. It is generally good to be wary of things that are superficially similar being used as proxies for one another...

HCIdivision17 10y ago

Oh no, my estimates were really in favor of the parent's comparison. That $600k is a lowest-bidder minimum, expecting to redo in a month when it fails. I'd be interested to know more about the breakdown, and I'd bet at least some municipalities are required to share it. A well trained road crew is likely pretty expensive, and as others noted, there's a lot more to a road than a driveway. Most driveways I've seen are largely cement planks, whereas a road is layers of differing materials to ensure frequent use doesn't destroy it too quickly. As for bridges. Eugh. I dunno. Those things are often crazy expensive. I wouldn't be surprised though, since that bridge is rather large and suffers a lot more wear and tear than NASA. I mean, they just need to punch a few one-time use rockets into space, but that bridge has to deal with thousands of semis. Space is a nasty place, but I'm betting thousands of trucks barreling over is harder to deal with year in and out.

Vraxx 10y ago

Just going off of the comment you're responding too, that $600,000 corresponds to one block when the original example specified 4 blocks for $1.5 mil. I don't claim to know anything about street paving economics, I just wanted to point out the disconnect.

zrail 10y ago

The load and traffic that a typical driveway sees is far less than what a city block would be expected to see. There's more concrete, rebar, gravel, etc for every square foot of surface. Interstate-grade highways have 8-10 inches of reinforced concrete. Driveways are typically 4 inches and are not reinforced. The same goes for asphalt, if that's what they're using. It'll be cheaper because it's not designed to last as long, but the scaling factors hold.

VLM 10y ago

Heaviest current production SUV is 6274 pounds for a Lincoln Navigator https://en.wikipedia.org/wiki/List_of_automotive_superlatives#Curb_Weight https://en.wikipedia.org/wiki/List_of_automotive_superlative... Federal interstate MINIMUM construction standard is to assume 105500 pound semi trucks. https://en.wikipedia.org/wiki/Federal_Bridge_Gross_Weight_Formula https://en.wikipedia.org/wiki/Federal_Bridge_Gross_Weight_Fo... IF you could get the big trucks off the roads, maybe use very small pickup sized autonomous self driving trucks running on and 3 inch thick concrete like a driveway, THEN $600K would probably be achievable. There are also correction factors that a SUV probably never exceeds 5 MPH on a driveway and usually doesn't park there and frankly most cheap driveways would be destroyed by a vehicle that heavy anyway, whereas the road has to survive 24x7 service at 75 MPH. The pounding the road takes at 75 MPH at 105500 pounds must simply be incredible.

HCIdivision17 10y ago
Fun trivia: road damage follows a fourth power law. [0] Double the weight and you do sixteen times the damage. [0] Link to link: http://www.vabike.org/vehicle-weight-and-road-damage/ http://www.vabike.org/vehicle-weight-and-road-damage/

ska 10y ago

Why would you assume that the paving on your driveway is fit for purpose on a public roadway? At the very minimum, load and wear patterns are vastly different. Drainage probably looks quite different also. I wouldn't be surprised if it requires a fundamentally different approach. Would you?

dclowd9901 10y ago
All I'm assuming is that building a road is a highly scalable operation, and it seems evidence backs that assumption up. There are an incredible amount of machines that are highly specialized in laying roads down. Does it require more than a residential driveway? Yes, ok. But why does it seem like costs rise exponentially with project size rather than logarithmically?
- ska 10y ago
  I'm more questioning whether your home driveway is in any way useful as a base cost estimate. I don't know either. But if it turns out that paving your driveway to the same standard would cost $100,000 the scaling looks much better. It is generally good to be wary of things that are superficially similar being used as proxies for one another...