Zoning and covenants are not a problem, so long as I keep the height
below 70 feet and can come up with a safe design.
> Rohn 65 as free standing???? However, you'll probably need an PE
> familiar with your soil/flooding conditions. I assume you have a zoning
> board to satisfy as well. It would be interesting if pilings would be
> necessary.... The work for your house...
>
> 73 de Brian/K3KO
>
> On 10/23/2013 16:38, Your Name wrote:
> > I am trying to determine if it would be practical to safely install a 40
>
> > to 50 foot free-standing or bracketed (not guyed) tower in my location.
> > I would like to hear from anyone who has erected a tower in a
similar area.
> >
> > My location is Chincoteague Island, Virginia, Zip Code 23336. If I am
> > reading the ?three second gust speed? maps correctly, this location is
> >
> > in a 120 mph area on the Exposure ?C? maps. However, the location is
>
> > also about a quarter-mile from open water (an inlet off the Chesapeake
> > Bay), so it is possible that it should be considered Exposure ?D?. The
> >
> > location is flat and barely above sea level, with no significant
> > features to obstruct wind.
> >
> > The soil quality is about as poor as possible from a support standpoint.
>
> > It is silty sand, and during the course of a year varies from dry/loose
> > to completely waterlogged. It is also mildly salt-contaminated(from
> > seawater flooding in 2012), and so rather corrosive. The ground water
> > table is high - holes deeper than 3-4 feet tend to fill with saltwater.
> >
> > One good thing: winters are relatively mild, frost depths never exceed
> > an inch or so. Ice storms are rare. Icing would not be expected to
> > exceed 1/4 - 1/2 inch at most, and ice storms have not been known to
> > occur at the same time as high winds.
> >
> > One final feature of the site: it is subject to tidal flooding during
> > severe tropical storms and nor?easters. Every 2 or 3 years, the base of
> > any tower at this site will be immersed for several hours in seawater,
> > to a height of up to 4 feet. (Most houses here, if you are wondering,
> > are elevated on pilings or perimeter walls.)
> >
> > Guying of the tower is absolutely not possible. Bracketing to my
> > residence (modern construction, concrete walls from the ground to four
> > feet, frame above four feet) may be possible.
> >
> > The total wind load of all equipment would be about 10 square feet.
> > I would install either a K4KIO Hex-Beam, a 2-element Steppir Yagi, or a
> > small tribander (Force 12 C-3S or similar) on the shortest practical
> > mast at the top of the tower. All of these have rated wind loads below
> > 6 square feet. A medium-sized rotator (Yaesu G-800 SA or equivalent)
> > would be used. I would probably also attach 1-2 fixed, omnidirectional
> > VHF/UHF antennas to the tower.
> >
> > My initial idea is to simply overengineer - select a tower rated for 120
>
> > mph at *double* my planned windload, and go up a step or two on the
> > usual foundation size. I'm also inclining toward an aluminium, rather
> > than steel, tower due to the saltwater corrosion issue.
> >
> > Any thoughts would be much appreciated. I might end up turning to a
> > Professional Engineer for final planning, but I'd like to check to see
> > if this is even remotely feasible before I incur that expense.
> >
> > Thanks,
> >
> > Jeff / KS4TL
> >
> > _______________________________________________
> >
> >
> >
> > _______________________________________________
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> > TowerTalk@contesting.com
> > http://lists.contesting.com/mailman/listinfo/towertalk
> >
> >
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10/22/13
> >
> >
> >
>
>
>
>
> -----
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> Version: 2012.0.2242 / Virus Database: 3222/6273 - Release Date: 10/22/13
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>
>
>
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