On 1/20/2015 10:34 AM, Patrick Greenlee wrote:
It can be done that way and is often easier, but construction sites
often have their own way of doing things. The soil around here is often
very moist (read, sloppy. The heavy concrete casting "sometimes" can
force its way through the muck that rapidly fills the bottom portion of
the hole. so for those conditions its easier, or even the only way.. A
form in the hole defeats the purpose of the concrete.
My front yard would be ideal for boring the hole and casting in place.
It'd never work in the back yard. In the NW corner, holes are
temporary. They last long enough that the casting could displace 2 or
even three feet of mud "if you hurry" but would be questionable as to
what you'd get with a pour.
As an example: I dug the holes for the guy anchors for my 100' 45G.
with the intention of making and installing forms the next morning and
doing the 3 pours in the afternoon. The problem was that the next
morning there were only two holes and a 10' wide depression, about a
foot deep where the hole had been for the NW guy anchor. It would have
worked if we had, had the form ready and dropped it in the hole. We
might have had to pump out the water but the hole would have still been
there. We didn't even need a form for the South hole.
My tower base http://www.rogerhalstead.com/ham_files/tower11.htm
Undisturbed soil was easily done!
and the hole that needed to be dug again
http://www.rogerhalstead.com/ham_files/tower12.htm It looks dry, but
believe me, it was only dry on top. It's almost like very wet Peat on
the side toward the camera.
We had no choice except to use a form, but Id make the forms differently
if doing it again. I'd set it up so as the pour filled the form the
internal braces could easily be pulled out. Getting those sides out was
a real PITA. I didn't worry about the braces. With the forms
back-filled before the pour and nature took car of at least half of
that, the sides could have easily been pulled up.after the concrete set.
OTOH if doing it again, I'd spend the money and go with a large crank-up
had I known I'd no longer be able to climb 7 years later..
The concrete in slop is still more effective than a single ground rod in
slop.
73
Roger (K8RI)
On 1/20/2015 2:46 AM, Roger (K8RI) on TT wrote:
The ones I have seen are formed by using a large cardboard tube as a
form to cast the ground rod in concrete. (remove the form before
planting the ground!) An auger digs a hole of the proper diameter to
the proper depth and the encased rod is lowered into place. Not
cheap, but very effective.
I don't get it. Why not augur the hole and place the rebar in it
(with proper clearance from dirt contact) and pour concrete into the
hole? Why complicate the process, adding the extra hassle and expense
of the Sonatube. The hole in the ground is a "wash", needed either
way but no heavy equipment needed to pick up the formed rebar filled
concrete cylinder and you don't buy and destroy a big sonatube
(cylindrical cardboard form typically used to extend a pier hole above
grade and similar.) Also it is much easier to pour concrete into a
hole in the ground than to fill a big sonatube.
Patrick NJ5G
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73
Roger (K8RI)
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