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[TowerTalk] Grouting a New Tower?

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Subject: [TowerTalk] Grouting a New Tower?
From: "Jim Thomson" <>
Date: Tue, 13 Dec 2011 19:06:47 -0800
List-post: <">>
Date: Tue, 13 Dec 2011 12:58:34 -0800
From: Grant Saviers <>
Subject: Re: [TowerTalk] Grouting a New Tower?

Have the same tower, I am wondering about the benefit of grouting, 
especially after taking down a TMM433 that had a lot of rust underneath 
the base plate as a result of the grouting.  My inspection of street 
light standards has been inconclusive 50/50 grout/no grout.  Same with 
cell towers with nuts under the base plates, mostly no grout.

Besides UST recommending it, why is it an advantage?

Grant  KZ1W

On 12/13/2011 11:48 AM, Steve Jones wrote:
> All-
> I recently put up a US Tower HDX-589 crank-up.  UST recommends grouting the
> the space between the base plate and the top of the foundation block.  I
> have purchased the proper non-shrink construction grout and am getting ready
> to do the job.  But I'm concerned because I used this stuff to patch my
> house foundation before, and it sets up so quickly I'm not sure how much I
> should mix up at a time.
> Any suggestions?
> 73,
> Steve
> N6SJ

###  I already went through that grouting business with my local structural 
eng.  [ HDX-689]
He sez it's an aesthetic thing....and perhaps will stop small creatures  from 
getting  in  below.
The major drawback is..... moisture and water  WILL  get in there 
eventually....and then the
same moisture can't get out !   It's  now trapped in there, and will just 
accumulate. My eng sez
DON'T  install the grout !   Complete waste of time, and adds no additional 
support either.
Leave it open, so it can breath. 

##  I started checking lamp posts  and also these 100' tall lamp posts used at 
sporting facilities.   80% have the grout.  I think in these cases, it's more 
of a tamper proof
security thing. IE: grout on all sides, so the nuts can't be accessed  from 
below by vandals.
On top, they will sometimes "double nut" them.  I doubled nutted on top, since 
I had loads of 
excess thread left, and the heavy duty nuts were not too expensive. 

## On a similar note,  I asked UST how much TQ  to put on those nuts. My 12 x 
threaded rods
are all 1.125"  and the nuts are huge things.  1  13/16" sockets and open end 
UST  sez... "snug tight".    What the hell does that mean?   I lubed all of 
mine with marine
grade  'never seize' [ nuts and rods] and initially cranked em up to 90 ft lbs. 
Portland bolt tells me you only require aprx 60% as much TQ  when threads are 
Big difference between TQ  and 'tightness' .    90 ft lbs  lubed is like  150 
ft lbs dry. 
Same deal on the 18 x transverse smaller 1" bolts, 6 per leg.. that hold the 
bottom section
to the base.  If u wreck those things, no big deal, they can be replaced.   The 
12 x embedded
rods can't be replaced, so until I find a better TQ number, I'm gonna leave em 
at 90-100 ft lbs.

Later... Jim   VE7RF


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