[TowerTalk] re: pouring concrete, finally!- a question

[Howard Dybedock]

At 03:47 PM 4/13/99 -0700, you wrote:
>In Rick's (KC5AJX) post, he mentioned that his holes were too deep. Now, 
>I'm not sure you can have too much concrete under a tower, but that's 
>another discussion. Anyway, his fix was to shovel loose excavate back 
>into the holes.  Now, I know that when you're pouring a footing for a
concrete basement 
>wall, you must pour onto undisturbed soil. Is the same true for towers?
73, kelly - VE4XT

Absolutely.   If the soil beneath the foundation is disturbed, it should be
compacted to the density of the undisturbed soil.  The easiest way to
handle this, especially in the absense of a compactor, is to remove the
disturbed soil and replace it with a uniform graded stone or gravel (clean
stone).

Placing a tower foundation on disturbed soil can result in settlement or
shifting of the concrete (leaning tower?)  )=o    Not good!

In the commercial tower construction business we often over-excavate, then
place in a layer of compacted gravel to supported forms, rebar cage and
anchor steel.  Keeps everything out of the mud.

Howard - AK9F


--
FAQ on WWW:               http://www.contesting.com/towertalkfaq.html
Submissions:              towertalk@contesting.com
Administrative requests:  towertalk-REQUEST@contesting.com
Problems:                 owner-towertalk@contesting.com
Search:                   http://www.contesting.com/km9p/search.htm