If the tower has angle iron type of legs, then you lower the tower
section into the hole after the rebar cage has been installed and
support it off the bottom of the pit with solid concrete bricks. If the
tower has round pipe like legs like Rohn towers, then the bottom of the
legs must be embedded into at least 6 inches of gravel. Condensation
water will accumulate inside of the legs and one must allow for this to
drain out or else it will accumulate, freeze in the winter, expand, and
pop open the legs. I wrap a little landscaping cloth over the legs'
bottom and secure it with cable ties to keep the stones from clogging up
the holes. Then guy the tower with guy wire or heavy ropes secured to
stakes driven into the ground or screw anchors, or whatever. But plan
to snug these up real tight, like you're going to keep it permanent.
Remember to have a crew member move around the concrete as it's being
poured or rent an electric vibrator to remove the air pockets that may
develop as the concrete tries to flow around the tower braces. Don't
over vibrate it though. Plumb before the pour and check and readjust
right after the pour; this is where extra crew is helpful so some can be
cleaning up concrete spills, washing equipment, and other re-plumbing.
Wait a week and remove all and start erecting! Be careful, wash any
concrete off the skin quick because it is akaline and is corrosive.
Phil KB9CRY
kenneth.lowrey@wright.edu wrote:
I am finally getting a tower after hamming for 41 years!!
I plan to pour cement around one tower section and use this as a base. The
township requires this procedure for the building permit.
My question is:
How do I keep this base section vertical while the cement is poured into the
hole? It seems to me that the force of the cement flow would push the tower
off plumb. Guy wires? Wood braces? I would appreciate any advice.
Thanks,
Ken
W8ND
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions and ask for Sherman, W2FLA.
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_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions and ask for Sherman, W2FLA.
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TowerTalk mailing list
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