Larry,
Looking at the turnbuckles this morning, it certainly seems more likely that
the bottom threaded shaft would bend before the anchor rod, which is a much
bigger piece of steel. If the shaft bends, I think it would become
impossible to turn the turnbuckles, which is bad.
I like the idea of pre-bending the anchor, but would like to get endorsement
of the idea from others on TT before trying it. What say, TT?
Although there's a fair amount of rod sticking out of the concrete and the
leverage is pretty good, it doesn't seem to me that I could bend the rod by
simply pushing. There's nothing nearby on which to secure a come-along. One
idea would be to use a backhoe to slowly apply pressure to align the rod.
The backhoe is returning to fill and tamp the holes next week. Good idea or
bad idea?
73, Dick WC1M
> -----Original Message-----
> From: Larry G [mailto:larry@k7mi.com]
> Sent: Saturday, September 23, 2006 1:28 AM
> To: wc1m@msn.com
> Subject: Re: [TowerTalk] Concrete in the ground! But...
>
> Hi Dick,
>
> COngrats on getting your project underway. I would not
> worry about the anchor but you should push on the rod after
> the concrete sets up to get it aimed at the tower to be sure
> there are no bending stresses on the turnbuckles.
>
> Larry K7MI
> www.k7mi.com
>
>
> ----- Original Message -----
> From: "Dick Green WC1M" <wc1m@msn.com>
> To: "Tower" <towertalk@contesting.com>
> Sent: Friday, September 22, 2006 10:16 PM
> Subject: [TowerTalk] Concrete in the ground! But...
>
>
> > Hi all,
> >
> > At long last, the concrete is in the ground for my 110'
> Rohn 55 tower!
> Whew,
> > that was a lot of work. And a lot of concrete -- 8 yards. I
> went with
> > 4d anchor specs, which doubles the hole size. Even then, we
> had some
> > problems digging "small" holes with an excavator and ran into some
> > ledge and big boulders. Took a lot of concrete to fix that. Some
> > photos and more details are posted on my website,
> www.wc1m.com, under Big Tower Project.
> >
> > Here's the "But...". The base is level. All the anchors are at 45
> > degrees and the equalizer plates are level. Two of the anchors are
> > pointing at the pier pin exactly on the compass heading I
> had planned.
> > But somehow one guy anchor is off about five degrees or so
> in azimuth,
> > so it doesn't point directly at the pier pin. In fact, it points
> > several feet to one side of
> it.
> >
> > I'm pretty sure we had it right before the pour. It's
> possible the rod
> > shifted during the pour, but I checked it several times and
> thought it
> > was aimed OK. The last time I checked it there was so much
> concrete in
> > the
> hole
> > I didn't think the rod could move anymore. One possibility
> is that the
> > weight of the bucket loader we used to shuttle concrete to
> the holes
> > slightly shifted the ground around the anchor, moving the whole
> > section of earth and the anchor rod with it (the bucket loader was
> > positioned between the rod and tower, fairly close to the
> rod.) Maybe
> > the shift happened
> after
> > I checked the rod, when he dumped the last load of concrete. At any
> > rate,
> I
> > didn't discover the angle error until the concrete had set enough to
> prevent
> > movement.
> >
> > For those of you wondering why the groove in the side of the hole
> > didn't hold the rod in place, this anchor is uphill from the base.
> > Consequently, the rod extends further above the surface
> than it would
> > on level ground,
> and
> > only a very shallow groove was needed to set the angle. Besides, if
> > I'm right about the effect of the bucket loader, a deeper groove
> > wouldn't have helped. BTW, the uphill rod in question is
> not the one
> > shown on my
> website.
> > That one is OK. I'll post pictures of the rod in question
> tomorrow if
> > I
> get
> > a chance.
> >
> > So, my question is... will 5-10 degrees of error in azimuth cause
> problems?
> > There's at least a yard and a half of concrete in that
> 6'x3'x4' hole,
> maybe
> > more. I don't think the slab is going anywhere. Seems to me
> the anchor
> > rod might bend a little. But the GAC3455 rods are very
> beefy. Even if
> > it bent
> a
> > little, I can't imagine it would be weakened enough to break. I'm
> > using 1/2"x12" eye-jaw turnbuckles. Could they be bent or
> damaged by
> > the angle error? Is this a problem, or am I just worrying over
> > nothing? Seems to me there's not a heck of lot I can do
> about it at this point!
> >
> > 73, Dick WC1M
> >
> > _______________________________________________
> >
> >
> >
> > _______________________________________________
> > TowerTalk mailing list
> > TowerTalk@contesting.com
> > http://lists.contesting.com/mailman/listinfo/towertalk
> >
> >
>
>
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