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Giant Concrete Arrows Across the American Landscape

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Re: Giant Concrete Arrows Across the American Landscape

#31

Post by 286c8cb04bda »

javert wrote: post #28
Sanddancer wrote: post #8

Earlier quoted context omitted.

These arrows, probably not so much, as they are pretty much all in the middle of nowhere. However, general concrete recycling is useful because breaking up existing, unused concrete for works projects tends to be cheaper than, and is more environmentally friendly than, quarrying.

I don't get it. Doesn't concrete crack and break in a messy way? How could it be re-used?

> How could it be re-used?

To somewhat over-simplify, concrete is made from three things: Cement, large aggregate (big rocks), and small aggregate (little rocks). Broken up concrete works pretty well as large aggregate.

Re: Giant Concrete Arrows Across the American Landscape

#32

Post by jff »

ChuckMcM wrote: post #14
mynameishere wrote: post #3

Even modern pilots (without GPS) use rivers and highways. Why couldn't 1920s pilots use railroads?

Modern joke "What do you mean by IFR" it means "I follow Roads"

With the extra joke being that following roads is actually VFR and that you most likely couldn't follow roads in IFR.

Re: Giant Concrete Arrows Across the American Landscape

#34

Post by sitkack »

dclusin wrote: post #23
phreanix wrote: post #17

I wonder what semi permanent structures we are building now that future generations will be looking at in 80+ years and wondering about our archaic technology.

The waste water storage tanks at the Fukushima nuclear plant will probably still be around and contaminated 80 years from now. Although I suspect that isn't exactly what you had in mind.

Just fill them with grain and have the birds eat it all. Problem gone.

Re: Giant Concrete Arrows Across the American Landscape

#35

Post by JshWright »

jff wrote: post #32
ChuckMcM wrote: post #14

Earlier quoted context omitted.

Modern joke "What do you mean by IFR" it means "I follow Roads"

With the extra joke being that following roads is actually VFR and that you most likely couldn't follow roads in IFR.

If that's the extra joke... What's the primary joke?

Re: Giant Concrete Arrows Across the American Landscape

#36

Post by gdw2 »

callmeed wrote: post #33

This is so cool. I'm taking my kids on a road trip around the west soon. Does anyone know of other cool, historical things like this we could hunt for?

Search the Twelve Mile Circle blog: http://www.howderfamily.com/blog/ . He covers many cool geo-odities.

Re: Giant Concrete Arrows Across the American Landscape

#38

Post by trafficlight »

jonah wrote: post #7

We had a tower with light in my town. We're right on the Pacific coast to the tower was inland and behind a hill so it couldn't be mistaken for a lighthouse by passing ships. The tower and shed are still there and are used for communication antennas.

All of the navigation beacons in Montana are still functioning.

http://mthistoryrevealed.blogspot.com/2013/03/guiding-lights...

Re: Giant Concrete Arrows Across the American Landscape

#39

Post by jff »

JshWright wrote: post #35
jff wrote: post #32

Earlier quoted context omitted.

With the extra joke being that following roads is actually VFR and that you most likely couldn't follow roads in IFR.

If that's the extra joke... What's the primary joke?

"Haha IFR is a fancy-sounding term but you really mean you just find a road and follow it to your destination as though you were in a car"
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