> On Oct 13, 2017, at 13:38, RMorris <robrk@nidhog.net> wrote:
>
>
>
> Sent from my iPad
>
>>
>>
>> ## pad + pier is a pita. The dirt you put back in there..around the pier,
>> that
>> sits on the concrete base is...free weight. You can easily dispense with the
>> form..but then you will use a helluva lot more concrete..which is OK per
>> Trylon.
>> But the re-bar setup is different.
>>
>> ## If ground is clay, or solid enough, so the sides of the hole dont cave
>> in,
>> you dont require the megabuck, pita wooden form. Flip side is.... the
>> wooden form
>> is very expensive to build. It comes out a wash, or close to it. Cost
>> of wooden form
>> vs cost of extra concrete.
>>
>> ## If a wooden form is used, it has to be carefully constructed. Concrete
>> weighs aprx
>> 4000 lbs per cubic yard....= 150 lbs per cubic foot. There is a huge
>> stress on the wooden form as is.
>> There is also a huge stress on the portion of the wooden form that
>> encompasses the pad. Thats from the
>> sheer vertical compression weight of the concrete in the pier. Get it
>> wrong...and form starts to come apart
>> when you have poured 80% of the concrete into the form.... u are in for a
>> rude awakening.
>>
>> ## Even if it all goes ok, the wooden form has to be removed.
Sorry, I fat fingered a reply, on the iPad.
Here’s how the big boys do piers…. Don’t need no wood.
https://www.sonotube.com/sonotubeconcreteforms.aspx
<https://www.sonotube.com/sonotubeconcreteforms.aspx>
Got to watch a 350 foot Rohn SS go up…
24x 24 foot hole, 40 yards of concrete. Pad and pier.
Each leg of the first section was 1100 pounds.
_______________________________________________
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
|