[TowerTalk] My first tower section is not plumb...

[Steve Maki]

Douglas,

Oh boy, at the risk of getting all the engineers and lawyers and 
would-be's in a dander, I'll suggest this - with the caveats that I 
don't really know what kind of tower sections you have other than your 
description that it's equivalent to Rohn 25. And I don't know whether 
you have an informed inherent feel for how much lateral stress your 
tower can handle.

But if I had 30' of *guyed* Rohn 25 sticking out of 1/2 cu. yd of 
concrete at a slight angle and for some reason absolutely needed to make 
it plumb, I'd do this:

1) I'd rig up a ratchet binder (come-along) or 2 in the appropriate 
direction(s) attached to to the top of the bottom section (10' or 15' 
up) and anchored out to solid attachment point(s).

2) I'd dig out all the way around the foundation.

3) I'd loosen the guy(s) in the direction(s) the tower is leaning.

4) I'd tighten the ratchet binder(s) to plumb the tower.

5) The best back-fill would be additional concrete all around. A 
*little* soupy would be best so it under-fills any new gap under the base.

6) Of course leave the ratchet binders in place and the loosened guys 
loosened until the new concrete is well set.

If your existing concrete is something like 2' x 2' x 3' deep, this 
should work. If it's a lot bigger or wider, it will be more of a problem.

Note: Personally I wouldn't worry about a little lean, but everyone has 
their own priorities.

Best,

-Steve K8LX

On 2/11/2016 6:51 PM, Douglas Ruz (CO8DM) wrote:

> Hi,
>
> I have been thinking and I am really want my tower straight and plumb.
>
> I am considering digging out some side of the base to adjust the tower
> level.
>
> Any tips or thoughts ???
>
> Can I just digging 2 sides or all 4 sides of tower bease???
>
> About backfilling...what is the best add concrete again for backfilling???
>
> what is the best method to move the base to adjust the level ??...it is
> about 2000 pounds base.
>
> Thanks in advance,
>
> 73....Douglas, CO8DM

>> If your tower is the equivalent of R25, and only 30', there's not much
>> you can do to it to really overstress it, unless you try real hard.
>>
>> But if you really want it straight AND plumb, consider digging out the
>> appropriate side of the foundation and letting the the concrete adjust
>> itself, and then backfilling it back in.
>>
>> At that point it will become what you want it to be, merely an
>> anti-sink device.
>>
>> -Steve K8LX