[TowerTalk] The tower base is poured BUT...

[David Robbins K1TTT]

> 
> > Doesn't anyone use forms any more???
> 
>     What for? I assume you mean below grade. The concrete is supposed
to
> be
> poured into 'undisturbed' earth.
> 
>     An exception would be when the walls keep sloughing; then the
forms
> would
> be necessary but you have to be real careful to backfill after you
remove
> the
> forms and tamp the backfilled dirt.
>

that is normal up here, due to rock and soil composition its almost
impossible to dig a hole of any specified size. and unless you are
building late in the summer when its been very dry the holes fill with
water and slough in.  and if its dry enough that they don't fill with
water the sides collapse when you walk near the tops.  the forms are
more to keep the dirt away from the rebar than hold the concrete in
place, but are usually necessary to get a reasonable size foundation
anyway... one thing I do try to do is the the side of the anchor holes
toward the tower as undisturbed as possible.  This usually annoys the
operators as they hate being told to dig a particular direction.
and yes, tamping backfill is a pain...  but even rohn's catalog
acknowledges that it is sometimes necessary and gives specs on how it
has to be done... forms have to be removed, tamp in 8" layers, density,
etc.


David Robbins K1TTT
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