On 7/13/18 11:35 AM, Richard (Rick) Karlquist wrote:
On 7/13/2018 7:14 AM, jimlux wrote:
On 7/13/18 6:11 AM, W0MU Mike Fatchett wrote:
They drive rebar in the ground with
a washer welded at the end for the tie offs.
> I doubt they have any signifcant pull-out strength, so if the wind
comes up, the stake will bend, pull out, and over the tower goes.
Probably true, although they are analogous to the big "tent stakes" used
to put up large temporary tents, and those have a successful track
record.
Those stakes are typically some fairly stiff steel and larger in
diameter (1"), known as "bull pricks" in the entertainment industry
(traditionally, they were rear axles, the gear providing a convenient
"head" upon which to hammer).
https://www.versalestore.com/p1959/30amp;quot;-Tie-Down-Ground-Anchor-(Bull-Prick).htm
A trick I use with guy stakes is to pound two of them
in about 3 feet apart. The stakes are long enough to allow them to
stick up 2 or 3 feet. A rope/cable is attached to the rear stake right
at ground level. The other end goes to the top of the front stake.
The guy goes to the bottom of the front stake. This gives tremendous
leverage and insurance against bending, pulling out, etc.
yeah, something like fence T-posts would work.
They too, are typically a stiffer steel than "rebar"
At my QTH, we have 100% clay, and as long as it is dry (which it always
is the 4th weekend in June) it is like concrete. I hired a D10 CAT to
try to rip this stuff up with a single 7 foot "knife" and the D10
(with 600 HP) actually stalled. The driver complained that he had
"only" 100 tons of weight to pull with. OTOH, during the winter rains
the clay has the consistency of peanut butter.
*real* temporary installations designed to withstand significant wind
(or seismic) loads will use auger screw anchors, or these days, I've
seen a lot of use of "big blocks of concrete" or K-rail/jersey barrier.
Before jumping to that solution, an intermediate solution is to use
a big pickup truck with a heavy duty trailer hitch parked at the
guy point. (The truck owner has to turn over the keys to the
field day captain for the weekend, to prevent one of "Murphy's
helpers" from driving the truck away. Hi.)
That works.. 5000# truck is the same as 5000# lump o' concrete.
i guess the net-net on all this is that guying a temporary tower
requires some amount of thought.
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