Having recently done this. I used two methods to keep the bolts in
place. First I put rebar in place just to wire tire the bolts to
correctly. But as everyone knows concrete is very heavy and moves
things around quite a bit during the pour. Someone suggested building a
wooden frame through which the bolts would be held in place during the
poor. I think that really helped me because I had to reposition the
rebar cage and anchor rods over and over to get everything to line up
correctly before the pour. Trick is to build the wooden frame so it not
only puts the bolts in the right place, but also doesn't get in the way
of pouring the concrete and any leveling work, and then being easily
removed afterwards. My little jig worked but didn't make for a pretty
top surface as I left the wooden frame in place a little longer than I
probably should have. But I didn't want to risk removing the wood too
soon and having the bolts move.
Oh and I asked an engineer about welding the bolts to the rebar cage and
was told NO. Not sure I understand that as it just seems like it would
make things a lot easier.
Noel
-----Original Message-----
From: towertalk-bounces@contesting.com
[mailto:towertalk-bounces@contesting.com] On Behalf Of Bill VanAlstyne
Sent: Friday, October 01, 2004 2:44 PM
To: TowerTalk List
Subject: Re: [TowerTalk] RE: Installing Tower Bolts
I remember reading somewhere recently -- and I'm going to research it
now, as I'm planning to pour a UST foundation soon myself -- that you
should NOT tie the bolts to the rebar, because you want the bolts to
transfer their loads directly and evenly to the concrete, not the rebar.
Anybody else have a recollection of reading that adminition?
Bill / W5WVO
Terry Dunlap wrote:
> This brings up a question that I've had for a while. It's always
> recommended that the bolts get tied to the rebar in a new base
> installation but it seems to be accepted
> practice to retrofit an
> existing base for a different tower by using epoxy anchors. These
> anchors
> aren't tied to the
> rebar in any way and would be the same as NOT tying bolts in a new
> pour. Isn't this a
> contradiction or at least an inconsistency?
>
> 73 de Terry KK6T
>
>
>
> At 10:28 AM 10/1/2004, FireBrick wrote:
>> As a licensed mason contractor I was frequently asked to help DIY
>> hams pour bases.
>>
>> wire tying rebar to the bolts is a must, both around the perimeter
>> and with diagonals across the center.
>> In addition, I used bolts above and below the bolt template, well
>> tightened.
>>
>> Those tricks took a few minutes to prepare, but saved many minutes
>> during and after the pour.
>>
>>
>> ----- Original Message ----- From: "Bill Turini" <wtu@cypress.com>
>> To: <towertalk@contesting.com>
>> Sent: Friday, October 01, 2004 12:18 PM
>> Subject: [TowerTalk] RE: Installing Tower Bolts
>>
>>
>>> There was a comment made regarding welding tower bolts together at
>>> the base to ease installation. I ran into problems with my recent
>>> installation and have a plan for my next tower base. :-)
>>>
>>> I built the base per the engineering drawings, and hung the 4' long
>>> bolts from the tower baseplate per the factory recommendation. When
>>> we poured the concrete into the hole, the bolts were just hanging
>>> there, flapping the the breeze, so to speak. We had to halt the pour
>>> to reposition the bolts three times, and they never did end up
>>> vertical.
>>>
>>> On the next tower, I'm going to tie rebar horizontally across the
>>> rebar cage and secure the bolts to it. That way they'll end up
>>> correctly spaced vertically and horizontally. As I said, they're
>>> very close, but we had a problem keeping them in position during the
>>> pour.
>>>
>>> As and aside, the concrete pumper got "constipated" during the pour.
>>> Boy, I never saw grown men work so fast to try to get it cleared! I
>>> guess the thought of all that concrete in the tube and the hopper
>>> was a bit daunting.
>>>
>>> The driver ended up calling in the firm owner and other drivers. I
>>> ended up with four folks from the concrete pump firm doing the pour.
>>> My contractor and his guys just stood and watched.
>>>
>>> Bill
>>>
>>> Bill Turini (425) 787-4477
>>> IT & Facilities Manager
>>> Cypress Semiconductor Lynnwood, WA 98037
>>>
>>>
>>> _______________________________________________
>>>
>>> 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.
>>>
>>> _______________________________________________
>>> TowerTalk mailing list
>>> TowerTalk@contesting.com
>>> http://lists.contesting.com/mailman/listinfo/towertalk
>>
>>
>> _______________________________________________
>>
>> 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.
>>
>> _______________________________________________
>> TowerTalk mailing list
>> TowerTalk@contesting.com
>> http://lists.contesting.com/mailman/listinfo/towertalk
>
> _______________________________________________
>
> 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.
>
> _______________________________________________
> TowerTalk mailing list
> TowerTalk@contesting.com
> http://lists.contesting.com/mailman/listinfo/towertalk
_______________________________________________
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.
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
_______________________________________________
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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