[TowerTalk] [BULK] - Re: Tower foundations

Wed May 25 20:46:21 EDT 2005

> I've never crowned the base, but then it never freezes here, and the flat
> base doesn't accumulate any puddles.
>
> An important step in the after-pour process, though, should be mentioned:
> Don't forget to engrave a date in the cement, using a stick or your finger
> or something.  The date should always be one that precedes the date when
> your municipality started regulating antenna towers.

I have the building permit instead. <:-))
Over 80 feet had to be engineered although they accepted the ROHN catalog 
specs.

Roger Halstead (K8RI and ARRL 40 year Life Member)
N833R - World's oldest Debonair CD-2
www.rogerhalstead.com
>
> For example, if your ordinance regarding antenna towers was written July
> 1968, your tower base should read, "MAY 68."
>
> This can help prevent problems...
>
> Oh yes, to make the cement look "old" (you know how cement keeps changing
> color with age, and for the first few years actually gets *lighter* in 
> color
> as it dries out?), while it's still a little bit tacky, rub some dirt into
> it.
>
> WB2WIK/6
>
> -----Original Message-----
> From: Keith Dutson [mailto:kdutson at sbcglobal.net]
> Sent: Wednesday, May 25, 2005 2:07 PM
> To: Towertalk at contesting.com
> Subject: [BULK] - Re: [TowerTalk] Tower foundations
>
>
> You know, I have heard this many times and completely agree with the need 
> to
> crown the base.  However, my base is flat as a pancake and there is
> absolutely no sign of any rust or other damage to the base of my 
> galvanized
> tower after 6 years.
>
> 73, Keith NM5G
>
> -----Original Message-----
> From: towertalk-bounces at contesting.com
> [mailto:towertalk-bounces at contesting.com] On Behalf Of Roger K8RI on Tower
> Sent: Wednesday, May 25, 2005 3:41 PM
> To: kr7x at comcast.net; Laurent Ferracci; TowerTalk at contesting.com
> Subject: Re: [TowerTalk] Tower foundations
>
>
>
>
>> Laurent:
>>
>> I appreciate your problem. The best thing to do is to extend the
>> concrete above ground so you can visually monitor the condition of the
>> base concerning rust.
>
> Another reason for doing this is drainage.  The top of the concrete should
> be "crowned" so any water tends to run off.
> http://www.rogerhalstead.com/ham_files/tower14.htm shows a good "crowned"
> concrete base.  The crown does not need to be this obvious, but it should 
> be
> enough to prevent any tendency for water to stay on the concrete.  The 
> base
> itself is much larger than the crowned portion, but water readily runs off
> and even several inches of standing water would not leave the actual tower
> in water.  However if I had several inches of standing water there, the
> tower would probably be the least of my worries.
>
> Roger Halstead (K8RI and ARRL 40 year Life Member) N833R - World's oldest
> Debonair CD-2 www.rogerhalstead.com
>>
>> I would leave the hole as it is. Pour the concrete to about 300 mm
>> below the surface. At that point I would make a form with the plan
>> dimensions need for the tower base. I would pour that size and would
>> extend it say 100 mm minimum above the potential ground surface. Slope
>> the top of the concrete to keep the standing water off and your set.
>>
>> Regards
>> Lonberg Design Group, Ltd.
>>
>> Hank Lonberg, P.E.,S.E. / KR7X
>> President
>>
>> -------------- Original message --------------
>>
>>> Dear OMs,
>>>
>>> My project is to erect a self supporting tower i bought a few monthes
>>> ago. The tower is 13 meters (36 ft) high and weights around 250 Kg. I
>>> planned to dig a square hole of 4x4x4 (based on what i read about
>>> similar towers), to put a rebar cage and a tower base into it, and to
>>> pour the concrete.
>>>
>>> However, reality differs from my plans, and i have a few questions.
>>> Please note that the tower has been "home made" (not by myself). I am
>>> confident in it but i can't simply "ask the tower manufacturer" my
>>> questions about the foundations. That's why i need your help.
>>>
>>> I asked one of my neighbour if he could dig the hole (he has machines
>>> for it). He accepted, and i explained him what i wanted.
>>> Unfortunately, he came one day with his machine while i wasn't here
>>> and dig (dug?) a hole that wasn't deep enough (just 2 ft). When he
>>> came back to check if that was OK, i told him that i needed twice
>>> that depth. He came back another day while i wasn't here (really bad
>>> luck) and dug again... i ended with a hole that is now too big ! It's 
>>> now
> 5x6 and of 7 ft depth.
>>>
>>> My first question is about the foundations dimensions. What do you
>>> think about them ? Does 4x4x4 seem sufficient to you, or should i keep
> 5x6x7 ?
>>> (of course, i could keep the big one as a "safety margin", but if
>>> 4x4x4 is already safe, i see no interest in paying the additionnal
>>> concrete it will take to fill the big hole).
>>>
>>> If a want a smaller hole, i can simply put back some ground (?) into
>>> it for less depth, but i can i do for a smaller "area" ? I could
>>> build a wood frame for the dimensions i want, put it into the hole,
>>> and put some ground around it, but i wonder if it will be sufficient,
>>> because when i'll pour concrete in the frame, it will have a great
>>> pressure from inside to outside.
>>>
>>> About the top of the concrete base: Usually, the concrete base is
>>> higher than ground level. What's the reason for this ? I would like
>>> better to have it lower than ground level. That way, i could have
>>> just the tower base coming upside. In my garden, 5x6 of grass would
>>> be nicer than 5x6 of concrete. Of course, rust on the tower base
>>> would be a concern, but if it's the only reason, i feel i can deal with
> it.
>>>
>>> About the tower base (to be sealed in the concrete). How deep should
>>> it go into the concrete ?
>>>
>>> Thanks for your help ( and sorry for my bad english)
>>>
>>> --
>>> Laurent F1JKJ
>>> _______________________________________________
>>>
>>> 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 at 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 at 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 at 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 at 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 at contesting.com
> http://lists.contesting.com/mailman/listinfo/towertalk
> 