> The Rohn concrete anchor rods are very heavy duty, but just in case I
> slathered several coats of roofing tar on the portions of the rod
> that were above the concrete block.
The alternative is to take a page from the bigger broadcast tower
installations and encase the guy rods in concrete.
73,
... Joe, W4TV
On 6/18/2013 9:13 PM, Dick Green WC1M wrote:
Any anchor that's exposed to soil is at risk of corrosion. Anchors
sunk in concrete are just as vulnerable because typically a good
portion of the anchor rod is not in the concrete -- it's in contract
with soil above the concrete footing. For example, Rohn spec calls
for my anchor footings to be poured in a 6-foot long by 3-foot wide
hole that's 4-feet deep. The concrete footings are only 18" deep, so
there's about 2.5 feet of soil that the anchor rod is in contact
with. Since the rod is set at an angle, probably 3-4 feet of the rod
is in contact with soil above the footing.
The Rohn concrete anchor rods are very heavy duty, but just in case I
slathered several coats of roofing tar on the portions of the rod
that were above the concrete block.
Regardless of the type of anchor rod you have, it's a really good
idea to inspect them every few years. That means digging down a bit
to see if there's corrosion.
73, Dick WC1M
_______________________________________________
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
|