I agree. I have rebar in my base.
The 45GSR (?, solid side rails) has a base with a short base in it and it
has
#7 rebar grid (12" c-c) at the top of concrete base and one at the bottom
but
no vertical rebar. Its base is bigger (4'6" square and 4 foot depth, 3 cu yd
of
concrete) but it handles much more load (something like 60 sq ft at 100
feet).
Bottom of the short base is 0-3" above the bottom of concrete base. I doubt
one needs a base that big for 45G as it is lighter but the 45GSR drawing
does
give a suggestion of what is needed for 45G with the short base - the rebar
grid
at top and bottom and a short base in probably only 2'6" square concrete
base.
73, Larry W6NWS
----- Original Message -----
From: "Mike Fatchett W0MU" <w0mu@w0mu.com>
To: <towertalk@contesting.com>
Sent: Friday, September 16, 2011 11:01 AM
Subject: Re: [TowerTalk] 45g Tower
>I would still build the rebar cage with or without the base section.
>
> On 9/16/2011 7:47 AM, Larry wrote:
>> The Rohn 45G brochure shows a round base 2'6" in diameter, 4 feet in the
>> ground,
>> with 6" above ground, with pier pin for towers up to 150' at 110mph wind.
>> Same
>> base is OK for up to 200' at lower wind speed. The base has 8 #7 vertical
>> rebar
>> in a circle plus some #4 rebar rings (1 cu yd of concrete). This all
>> depends
>> on soil
>> conditions, local codes, etc of course.
>>
>> The brochure also says one could make a square base 2'6" on a side. No
>> mention
>> of using the short base in concrete and how it might affect the rebar
>> schedule.
>>
>> I have a square base on my 100 foot 45G with concrete ending slightly
>> above
>> the
>> bottom of the legs in gravel on a short base. It has made it through a
>> couple of hurricanes
>> and a tornado so far without problems.
>>
>> 73, Larry W6NWS
>> ----- Original Message -----
>> From: "Stan Stockton"<stan@aqity.com>
>> To:<towertalk@contesting.com>;<starrose444@aol.com>
>> Sent: Thursday, September 15, 2011 9:08 AM
>> Subject: Re: [TowerTalk] 45g Tower
>>
>>
>>> Bob,
>>>
>>> All this is just opinion:
>>>
>>> I suggest that you consider putting up one tower and making it about 85
>>> feet tall. There would be four fewer holes to dig, fill with anchors,
>>> concrete, etc. You would only need two sets of guy wires (same as what
>>> you were planning except all on one tower) and whatever you will put up
>>> will be overall better at that height than at 35 feet. You would have
>>> the option of antennas at lower heights either fixed in one direction or
>>> rotating with a side arm.
>>>
>>> Unless you are on top of a hill with a steep drop off near the tower,
>>> where an antenna may actually work better at 40 feet than at 80 feet,
>>> the elevation above sea level makes little difference except for its
>>> relation to surrounding area and line of sight communications. In other
>>> words someone on a little 100 foot hill surrounded by sea level is in a
>>> much better location than someone on flat land for miles in every
>>> direction at 2000 feet elevation.
>>>
>>> As far as the base is concerned I think 5 feet deep is way overkill.
>>> For a guyed tower, all you are trying to do is keep the thing from
>>> sinking. Check the source who said 5 feet is needed and see what they
>>> say about 3 feet versus 5 feet.
>>>
>>> Stan, K5GO
>>>
>>>
>>> ----- Original Message -----
>>> From:<starrose444@aol.com>
>>> To:<towertalk@contesting.com>
>>> Sent: Wednesday, September 14, 2011 6:05 PM
>>> Subject: [TowerTalk] 45g Tower
>>>
>>>
>>>> Again thanks for all the information about using a mid section for a
>>>> base.This is my first tower so I want to do it right.I have 8 10ft 45g
>>>> sections and one 45ag top section would like to make two towers.Each
>>>> tower will only be about 35-45 feet in height I am elevated at 1100
>>>> feet now on a very large farm.I was told the hole should be about 3x3
>>>> and 5 feet deep.They will not be aginst the house so I have two sets
>>>> of guy wires Iam thinking a set on each?Any information like how much
>>>> gravel in the hole grounding etc.
>>>>
>>>>
>>>>
>>>>
>>>>
>>>> Thanks
>>>> Bob
>>>> Kc8phb
>>>> _______________________________________________
>>>>
>>>>
>>>>
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>>> _______________________________________________
>>>
>>>
>>>
>>> _______________________________________________
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>>>
>>
>> _______________________________________________
>>
>>
>>
>> _______________________________________________
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>
> --
> J6/W0MU November 21 - December 1 2011 CQ WW DX CW
>
> _______________________________________________
>
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