Metal Pipe Fence Leaning

[AchingBack]

wroughtn_harv mentioned cone shaped holes as one of the problems with posts being heaved. He is right on. The holes should be wider at the bottom than at the top. That is hard to do with an auger, but easy with a manual post hole digger. This method will greatly reduce post heave.

 

[ToadHill]

In this part of the country I like to use construction tubes, put them into the hole and fill with concrete around the pipe. This gives the sides a nice smooth surface and the expanding soil or frost heave has nothing to grab onto.

Since I've used these I've never had any problems with frost heave, even after many years when the paper tubes rot away the concrete is still smooth and it resists heave just as well.

 

[jnealhicks]

Hi: First post to this forum, so apologies is this is in the wrong place.

I too have a pipe fence, leaning about 15 to as much as 30 degrees. I'll describe what I'm doing here--hopefully the less experienced can pick up a hint, and the more experienced a laugh at my screw-ups.

This is in Fairview texas, with clay soil. As far as I know, fence was installed in mid '80s. I don't have a tractor to pull it straight, or a truck (which may be enough to have me deported from TX, so please keep this to yourselves), and it leans so far I wasn't sure if it could be pulled straight in the first place without destroying it. If that's successful, then I'll move on to a strategy to keep it straight.

The first of two sections to be straightened is about 150 feet, with 6 inch posts at each end.

First I laid down 1/2 in. poly pipe, with little drip sprinklers at each posts, and let it soak overnight. Next morning, at the base of each post, I dug a 12-18 inch-deep half circle. I took four boards, each 5-6 long (stuff I had laying around, a 2 x 12, couple of 4x4 posts, coupl of 2x4s nailed together to make a 4x4), and laid them on the ground, perpendicular to the fence line, abutting to the post. At the end of each post/board, I screwed in earth anchors--essentially a big eye-bolt with an auger on the end. Got these at a 'tractor supply' store, and then cheaper at another shop (rhymes with 'Ranger'). First used 40 inch anchors, then swithed to 30 inch because turning 40 inches all the way into the ground takes A LOT of effort.

So there's a fence post, a board lying perpendicular on the ground, abutting to the post, and an earth anchor screwed into the ground at the end of the board. Then I used a come-along, with one end hooked to the earth anchor, and the other end hooked to the top fence rail, thus making a trialnge with the three sides: 1) fence post, 2) board on the ground, and 3) come-along cable. I ratcheted and darned if it didn't immediately begin to straighten out the fence.

As I mentioned, however, I have 150 feet in total, and the other panels weren't straightening. I duplicated the set-up a few posts down the fence line, and got the same good result. I will add 2 more of these set-ups, then hope to pull straight the whole 150 feet. So far, I've reduced the lean by half, but don't want to pull harder until I have all 4 come-alongs attached.

Next thing (assuming I can pull it straight) will be to figure out how to keep it that way. I'm thinking of additional concrete around the posts, without a shoulder as per Wrought_n_harv, plus a couple of 6 foot t-posts, say 2-3, pounded straight down, then welded to the fence posts.

Life's hard (and expensive) without heavy equipment!

Total costs so far:
$60 plus tax for 4 cheap come-alongs
$30 for earth anchors
$50 for chain, cable, hooks
$40 for poly pipe and fittings

 

[jnealhicks]

Replying to my own post, I just now noticed Cat Driver had suggested the same strategy a year ago--i.e. using an anchor, and a come along to pull it straight. I plan to use four over a 150 foot stretch--these are 4,000 pound come alongs, and I haven't pulled it entirely straight yet, but I can say the cables get VERY tight, and I'm not sure if I'm below, at, or above the 4,000 pund limit. Other than that, it seems to be working so far . . .

 

[ChevyHDGert]

I haven't yet done anything with mine. Other priorities like getting the house built out there, then I can spend my evenings "fixing up" the place.

I'd rather not anchor mine if possible only because that would be one more thing to have to weed eat and shred around.

 

[jnealhicks]

As an update to my post in 2010--can't believe it's been that long--the straightening I did has held up--still straight.

I also tackled another 150 foot section over the weekend, and with the experience of doing it once, it went much smoother this time, and with much less effort. I don't have a tractor to pull it, but the manual method works well so far. Real simple, just dig out a little on the side it's leaning away from, and toward which it needs to move. I used 2 come-alongs on the leaning side, and 2x4's on the other side. I pushed the fence straight from one side, while my helper cranked the come-along from the other side. I used the 2x4s to help hold the progress, from the leaning side. Then went up and down, back and forth, over the 150 foot section, pushing it straight straight a little at a time, cranking the come-along a notch or two at a time to hold the progress. I also put water in the holes to soften the soil. I used two come-alongs (placed 1/3 of the way, 50 feet apart), and about 10 2x4s (notched with a "V" on one end to cradle the pipe) to prevent it from leaning back, and take the strain off the come-along and rebar/anchor.

For anchors, I used rebar bent at one end so I could fasten the come-along hook to it. Last time I used "earth anchors" but you have to 'drill' them all the way down (by hand), and all the way out (by hand) when finished--last time that was the most strenuous part of the job. With rebar, I just bent one end, drove it into the ground at an angle, and easily pulled them out when done--way easier than the earth anchors, and if you straighten the fence little-by-little (like 3-4 inches at a time) with the come-along, and use the 2x4s on the other side, the force on the anchor/rebar is minimal, and they did not pull up out of the ground.

With this combination of come-alongs, 2x4s, water, and digging, it was no trouble at all--probably about 5 hours at an easy pace for the whole straightening job--with the digging and tree root cutting by far the toughest part. I did use a considerable amount of cement, though, on the 2010 job. Took the advice here to use bell-shaped holes, and avoided creating a 'shoulder' and have experienced no heave after 3 winters. Next time I do this, I will dig out even less from the leaning side--the original (leaning) posts were sunk in about 30" of concrete, and digging out about 10" of that would be enough, I think, assuming you add some water. That will cut down on cement use as well.

Just a few other things about this particular situation: I've seen some recommend taking off the old cement from around the pipe--haven't done that, and have experienced no problem in the first 4 years after the straightening. Some of my holes had 'shoulders' (cone shaped) but no problem so far with heaving, even though the last few winters have been cold (minimum temps in low teens, and a few times down into the single digits). Based only what a come-along will do, I think a tractor would easily break the welds if not done carefully.

 

[txdoc42]

jnealhicks- Thanks for your update. I searched far and wide for methods of straightening fence, but all of the advice I found was for wood or t-post. I am gearing up to tackle about 1700 feet (eek!) of leaning pipe fence this fall and will use your method for most of it, even with access to a tractor. There are too many long stretches where I'd need a second tractor to get it even.

-Doc