David Thompson wrote:
> Most of the new highway light poles (at least around Atlanta) are what a GA
> Power Engineer calls composite poles. These are a combination of concrete
> and a metal. They are not crank up but come in 40 foot lengths. You can
> combine the lengths by using a big bolt to tie them together (may be two or
> four bolts depending on height and structure planned for the top.
>
> I watched them put up one at the corner near me which is a busy intersection
> and they used two bolts and put a small camera at or near the top. A second
> was just one stalk (to use the Engineers term) and this holds up the traffic
> lights. These are put into the ground just like a wood pole with 8 feet per
> 40 foot stalk. I have also seen some that mount on a concrete base with a
> separate mounting base and heavy duty hardware. These are typically tall
> slender poles that hold a street light. I remember Frank Cassen, W4WBK (now
> SK) worked for a Design firm in Memphis who designed these intersection
> poles (in 1970) and the hard part was building strength into the base mount
> for high winds.
>
> The price varies based on the diameter required but the Engineer said they
> were much more expensive than wooden poles which go for about $2,000 for a
> 120 foot stick (again using GA Power terms). The Engineer pointed out
> wooden poles require EPA remediation upon replacement and that is why the
> are often willing to give them away.
>
> Just like a wooden poles, they use bucket trucks or cranes to have access to
> the top. It appeared to me that regardless of the price, the equipment to
> put up a 80 footer (actually 68 feet) is quite extensive.
>
> Flag poles are all aluminum so are therefore very expensive.
Since all these schemes require some amount of "engineering" (i.e. it's
not like a radio tower where it comes with a set of sealed drawings
including the installation method), one could probably have your
engineer (who would be required to design the base) just spec out
appropriate sizes of steel/iron pipe which gets welded up with the
requisite flanges.
The commercial light poles are convenient (for a traffic department)
because they are mass produced. Instead of spending time individually
engineering each installation, they get some economy of scale, and don't
have to hassle with the fabrication of the actual pole.
You could probably go to a commercial pipe fabricator and have them make
up sections up to 40 feet long with standard bolt flanges on each end.
All nicely welded by certified welders and machines. Your big cost is
going to be the steel and the installation.
A 21 foot length of Sch40 10" pipe (10.75 OD, .365 wall) is about $500.
This is probably overkill, but gives you an example.. The cost is
probably fairly linear with mass. (i.e. a 5" pipe would be 1/4 the cost)
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