Earth Anchors

[GaryM]

I'm planning to install a 70' radio tower on my property in the spring. It's guyed with Kevlar guys anchored with Earth Anchors (or augers if you prefer) just like those used for anchoring mobile homes. The ones I'll be using are 8 inch diameter and 48" long. They should be installed with the eye pointing to the top of the tower. So they will be inclined at about 40 degrees off the vertical.

Any ideas on screwing these things into the ground? The ground seems to have no rocks of major size, so I don't think that's an issue.

I'm considering substituting a concrete filled hole of about 12" dia and maybe four feet deep with an eyebolt anchored in the pour. I'd extend the pier a foot or so above grade to make it easier to trim the grass.

Any ideas for installation of the anchors. If they were vertical I'd try and rig a way to turn then with a 3p PHD.

 

[Egon]

Why do the anchors have to be angled so they point to the top of the tower? Exspecially the concrete ones?

Egon

 

[Mike_Dumond]

Egon, it's so the strain is in line with the pin. If they were vertical, over time the swaying of the tower would pull them in towards the center, causing loose guys and more swaying.

73's de WA1ZPD

 

[Anonymous Poster]

Screw in anchors should NOT be installed pointing in the direction of the object they will anchor, they should be installed by screwing them in vertical. This is the standard for any type of anchor. After screwing the anchor in, a slot is cut with a digging bar so the anchor rod can be tilted in the direction of the object being anchored.
This enables the anchor to pull against virgin soil.
Screw anchors will need to be retensioned after a period of time as they continue to align themselves with the tower.
Screw anchors can be installed with an adaptor on an anchor, or by inserting a digging bar thru the eye and walking in circles.

 

[Mike_Dumond]

Gary, I'd go with the anchors, personally speaking. We've done some towers up here with both, and they work equally well. However the anchors came in at a lower cost. We had the power company run some in for a couple of the towers. Takes them just a few minutes to do it. Down side was working around their schedule, which wasn't too bad.

73's de WA1ZPD

 

[Mike_Dumond]

Franz, I'll go with the power company's recomendation on this one. After all, they do it for a living./w3tcompact/icons/laugh.gif

 

[GaryM]

Mike,

Thanks for the advice. I'm planning on a Glen Martin 70' with the Voyager tram system. I'd rather have a self supporting tower, but I really like the idea of not having to climb it either.

I didn't know about the trick of screwing it in vertical and then leaning it over. But it makes sense.

Gary, W0GOM

 

[Mike_Dumond]

Gary, the vertical installation is easier if you're doing it by hand, but if you can get the power company to do it using their anchors, I guarantee it won't move. Those things are 8 feet long. Maybe you can find a ham who works for them, make it easier to schedule.

 

[Mike_Dumond]

Of course, if you were closer, I'd go give you a hand, just so I could drool over your setup.

 

[Mosey]

One trick that might help if you have hard soil is to wet the ground before screwing the anchors in. Soak the area with a garden hose for about 5 minutes, then start screwing the anchor in. When it gets too hard to turn, put the hose on it again for 5 more minutes. The water will go right down to the end of the anchor by following the existing slot and loosen up the soil at the bottom. I have to admit I've never tried this on anything 48" long, but it sure has worked good on shorter ones! I was amazed what a difference it made the first time I tried it.

N4IMO