If they make fiberglass guy lines, why can't they make fiberglass anchors?
Chris
KF7p
On Jun 20, 2013, at 10:38 AM, Hans Hammarquist wrote:
> What I have seen, it is only the portion closest to the surface that
> corrodes. I have found iron pieces buried for hundred of years with only
> slight corrosion. Scrap iron, stored laying on the ground, has almost
> disappeared in no time. I believe it is a combination of water, "dirt", and
> air that is causing this.
>
>
> When installing fence with steel poles, a concrete "plate" is made around the
> pole just at the surface. It is sloped on the top to allow water run-off. If
> you don't do that the pole will corrode at the surface and eventually break
> there.
>
>
> The rebar in concrete is "protected" by the concrete but will corrode if too
> close to the surface. In the same way the fence pole is "protected" by the
> concrete plate.
>
>
> Maybe some concrete poured around anchor can extend the life-expectancy of
> the anchor.
>
>
> Next: What method or how would you inspect an anchor for corrosion damages?
> Just digging around it?
>
>
> Hans - N2JFS
>
>
>
> -----Original Message-----
> From: Mark Robinson <markrob@mindspring.com>
> To: Jim Thomson <jim.thom@telus.net>; towertalk <towertalk@contesting.com>
> Sent: Thu, Jun 20, 2013 11:36 am
> Subject: Re: [TowerTalk] Screw Anchor Experience
>
>
> Jim wrote
>
>
>> ## why mess with screw in anchors ? Only power company’s + telco’s use
>> em. Even then
>> they use eggs in the EHS guys. A 40’ tall utlility pole is already 6
>> feet into the ground. No
>> anodes used.
>>
>> ## The rohn type rod anchors are in contact with the soil, where it is
>> trenched, so that portion
>> of the rod needs to be coated with roofing tar pitch. Those GAC series
>> anchor rods involve
>> excavating a huge hole, that is then trenched. The concrete slab needs to
>> be poured, then the
>> entire mess is bakfilled with dirt.
>>
>
> I reply...
>
> They weren't screw anchors. They were the Rohn supplied anchors set in
> concrete per the Rohn specifcations (as you describee) BUT they are still
> vulnerable to corrosion. I have read dubious accounts of using tar on the
> buried metal parts - the tar can fail and then the corrosion will be
> concentrated in the failed areas
>
> My opinion/guess is that the sacrificial anodes are a better way to go but
> only time will prove me right or wrong.
>
>
>
> Mark N1UK
>
>
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