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Utility wood pole repair

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SKJ25POL

Structural
Mar 4, 2011
358

I have a wood pole (guyed) deadend that has a decay in ground level.
I learned there are c-truss, c2 - truss, and et-truss.
I couldn't find a table or catalog different sizes of these repair metals.
How they are classified, which one do we use for what cases?

What location do we put them? Shall we put in orientation that covers the decayed hole? or there are specific location we put them?
What thicknesses they come from? and how do we chose the right one? How do we specify their length?
Any information is appreciated.

Skj
 
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They're specialty items. Call the manufacturer and get their information on rating, installation requirements and similar. Then review their recommendations, do your own independent check and go from there.

This isn't a new problem, don't reinvent it.
 
I've never heard of those classifications, but I don't know where you are in the world (Btw, can anyone clue me in as to where to find that info?), but the classes of poles in the US that we deal with are 5 thru 1 and then H1 thru H6, in ascending order of bending capacity. The diameters vary by species, i.e. a class 3, 50ft pole in Douglas Fir is smaller than a Red Pine one, but they have the same bending capacity because Douglas Fir has a higher allowable bending stress.

I think your best bet is to contact a utility pole supplier, who can give you the specs for the different classes of poles. You may have to go to your governing code for the allowable stresses, load factors, etc. Just be sure you're using diameters and allowable stresses for the same species, and you should be able to specify a pole just by class and length.
 
HotRod10:
Double click on the poster’s handle in the thread. This will take you to their profile, such as it is. The last item in the profile para. is an indication of where the person is posting from, at least where the server which serves their account is located. This is (their location is) not always 100% accurate, since they may have an account which moves from place to place with them, or the home office is in Calif. while they are located in NY. Your's is (WY, US)
 
HotRod,

He's not installing new poles. He's retrofitting existing deteriorated poles using proprietary retrofit systems. They're basically corrugated plate (think tribeam traffic barrier type things) that you strap onto the outside of the pole over the distance that you're trying to strengthen.
 
Thanks dhengr.

TLHS, I see that now that you pointed it out. Seems like a lot of work and more expense than just replacing the pole, but they must have their uses, or they wouldn't be on the market, I suppose. We did something similar once for a steel high mast light tower. The base section had cracks in the welds around the access hole. It cost more to have the crew drill the 900 or so holes to bolt on the steel jacket than it would have to replace the section. Apparently, the engineer was unaware the sections could be separated.
 
It can be cheaper depending on the situation. The material costs of replacing a pole may be lower, but the additional work involved in temporarily restraining the system, doing work on the live lines, co-ordinating the several different utilities that might be using a pole and all of that fun stuff adds up really really quickly. You can spend a lot of money on co-ordination, planning and different guys who have to do their half hour job.

It all also depends on the reliability expectations. Replacing a pole may be better long term, but depending on the importance of a pole it might make financial sense to patch it together for a while.
 
Makes sense, TLHS, especially with consideration of trying to work with live lines.
 
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