[TowerTalk] LOOKING FOR A USED CRANK UP SELFSUPPORTINGTUBULARTOWER

[Dan Kovatch]

My US tower anchor bolts which were installed about a year ago had two nots 
locked against each other threaded onto the bottom of the straight rod and 
the thread end was 'peaned' over. No welding in effect.

FWIW
Dan W8CAR

----- Original Message ----- 
From: "darrel" <darrel at vanbuer.net>
To: <rmoodyg at bellsouth.net>
Cc: <towertalk at contesting.com>
Sent: Wednesday, February 01, 2006 12:37 PM
Subject: Re: [TowerTalk] LOOKING FOR A USED CRANK UP 
SELFSUPPORTINGTUBULARTOWER


> It also shows straight bolts on their foundation drawings.
>
> But they DO have a nut and washer welded? on the end to keep it embedded.
>
> I have no idea whether epoxying a straight rod into a drilled hole has the
> same pullout resistance as a J-bolt or nut and washer (it's not enough 
> that
> the epoxy is stronger than concrete - it's adhesion to the bolt is 
> critical -
> rebar is bumpy so that the concrete gets a good grip), but a couple of 
> these
> bolts do take the entire uplift force on the upwind side with a 70 foot 
> long
> lever arm (rough estimate 20,000 pounds per bolt, a good fraction of it's
> breaking strength).
> My guess (but I have no structural qualifications), is that the J bolt 
> (or
> washered straight bolt) snaps long before you could pulverize enough 
> concrete
> to pull it out.
> As to the change - I'd guess the found the price of J bolts higher than 
> the
> current choice and either way pullout wasn't the first failure.
>  Darrel AK6I
>
> --- "Richard M. Gillingham" <rmoodyg at bellsouth.net> wrote:
>> They're shipping straight bolts now.  I just received mine a couple of
>> weeks
>> ago.
>>
>> 73
>> Gil, W1RG
>> ----- Original Message ----- 
>> From: "Jim McDonald" <jim at n7us.net>
>> To: <towertalk at contesting.com>
>> Sent: Wednesday, February 01, 2006 11:31 AM
>> Subject: Re: [TowerTalk] LOOKING FOR A USED CRANK UP SELF
>> SUPPORTINGTUBULARTOWER
>>
>>
>> > Doesn't US Tower require J-bolts, rather than straight bolts?
>> >
>> >
>> > Jim N7US
>> >
>
> _______________________________________________
>
>
>
> _______________________________________________
> TowerTalk mailing list
> TowerTalk at contesting.com
> http://lists.contesting.com/mailman/listinfo/towertalk
>
>
>
> __________________________________________________________
> Message transport security by GatewayDefender.com
> 1:30:53 PM ET - 2/1/2006