In a message dated 11/2/01 4:07:50 PM Pacific Standard Time,
n2mg@contesting.com writes:<<
Not sure of the arrangement you are proposing...
If you are attempting to co-locate two of these near
each other, and tie all the guys to the pair, I don't
think that you'd get much of an improvement. First, I
don't know how you'd effectively connect guys to two
anchors at once. More importantly, if I understand
how they work, the screw anchors rely on a volume of
soil (I think approximating an inverted cone) above
the disk to hold them in the ground against the
pulling force of the guy wires. If you locate two
anchors near each other, IOW, so that these volumes
overlap, you would NOT get 2X holding power.
You should get the expected improvement if you
separated the guys (assuming you have more than one
guy level) and put the top guy on one anchor, and the
lower levels on another anchor (that's located closer
to the tower).
73 Mike N2MG
> wa3gin@erols.com wrote:
> Wondering if I can use two per cable to increase the
> ratings? My soil is sandy loam...
> thanks, dave wa3gin
<< >>
Dave: That is a "Great Idea." Do that for the top guys--just to be sure
for the time when there is "ice loading in high winds." I had thought of
adding a larger steel disk over the disk at the end of the anchor rod. It
does require a bigger hole just to get it in. k7gco >>
It's assumed that the spacing between them is far enough so the inverted
cones of dirt above the disks don't overlap. I visualized one anchor behind
the other about 10'. Many many many years ago ARRL had in their Antenna
Handbooks a simple technique I've used many times. They showed a stake in
the ground that a guy wire was attached to. To enhance it's holding ability,
another stake was driven in the ground about a foot behind with a connection
between the top of the 1st stake to the bottom of the stake in the back
sticking out of the ground. This "double staking" really increases the load
it can safely take. I visualize the same proportional load increase 2 guy
anchors one behind the other could handle which would be very useful in soft
ground of any kind and insurance for that one extra load of the "big wind" in
the summer and the "big wind in the winter with ice loading." A frozen
ground should give a more secure ground in the winter. Cross bars can be
driven in at an angle over the guy anchor to extend and beef up its inverted
cone of conversed dirt above the disk at the bottom of the guy anchor.
A couple of years ago Spencer SD had the tornado that wiped out 1/3 of
it--22 miles from my SD home. The winds around it were strong also. In the
spring with normal rains the ground is soft and anchors can pull out with
enough pull.
There was an incident that "caught my full attention" while riding Amtrak
back to Seattle one spring of heavier rains than normal. There was water
standing all over, basements leaking and farmers unable to get in their
fields. The train was slowing done frequently in particular around curves
more than normal and other slow going more than normal. The railroad bed is
about 5' above ground level and fields were full of water.
What really got me was there was a stretch of "Straight Track" about 3 miles
long where we slowed down about to 30 MPH--while tilted at about 10-15
degrees. Since when are straight track runs tilted? This is a piece of very
bad track bed when "straight runs are tilted." Guy wire anchors weren't too
secure at this time and I heard of some pulling out.
I asked about this stretch of canted track and if they planed to get it
leveled out? I was told "that they rent the track from the Freight Rail
people". I rode Amtrak in the winter one time in another route and they
didn't hardly slow down at all in comparison. The car is starting to look
like a safer way to travel all the time. K7GCO
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