Temporary Piling Crane

[csr0831]

Gents.....

I have about 15, 8 inch by 16 foot pilings to jet down on my bulkhead. Parts of it have failed and I need to rebuild. It's my understanding these piles weigh in at about 250 - 300 lbs a peace. I need to be able to stand them up and postion them so I can jet them in. I have given this a little thought and have come up with an idea using two 4x4x10's, some cable, a chain fall and some fittings to build a temporary crane (for lack of a better word) to stand these thiings up and get them started. The rig would be disassembled and moved to the next location when done with each one. I would like for those of you with some structral experance to give these drawings a look and give me some feedback on wheather this will work...safely...specifically, will the 4x4's handle the load?

I appoligize for the drawings as they are not to scale and are rough at best. I think I have all the measurements and specs in them to form an opinion. Thanks gents, I do appreciate it!

 

[Shield Arc]

A lot of work, have you checked into renting a boom truck for a day? Or can you get a truck close enough?

 

[csr0831]

Bulkhead is in my backyard...I would have to remove a fence and the truck would have to drive over drain fields and septic tanks...not willing to take that risk as they are about 60 years old.....last thing I want to do is pull a truck out of the hockie tank! I did consider it, but I think I am going with the lesser of two potential evils.....

 

[Shield Arc]

Oh that sounds like nothing but trouble. Even a forklift will play havoc on a drain field!

 

[dfkrug]

I did a similar thing when I set the ridge beams for my house.

I used 20-ft steel angle steel that was 2x2x1/4", bolted at the top.
All were lifted with a 2T HF chain hoist. My beams were steel I-beams
weighing 300-400# each.

Since the 3 legs are almost vertical, they can handle many hundreds of
pounds of weight. Just be careful that the center-of-gravity of the
load does not get outside of your pyramid.

 

[csr0831]

The center of gravity WILL be outside the pyramid, but the third "leg" is actually a peice of stainless steel cable that will be tied back to an anchor...this will allow me to control the angle of the other two legs which will extend beyond the bulkhead slightly.

 

[Shield Arc]

One thing I'd suggest, is use at least 3" x 3" x 3/8" or 1/2" plate washers on both side of your bolts. Malleable washers are OK, but I've broke them before, so I always use plate washers.

 

[csr0831]

Agreed. I did not show them in the drawing, but it was my intent to do so. Thanks for the comment!

 

[Baby Grand]

Not familiar with the soil you are setting the gin pole (that's what this looks like to me) legs on. From the angles, load distribution should dig them in, but if there's any doubt they may try to slide on the surface, I'd make sure they had some sort of anchorage. Last thing you want is a "rapidly changing wheel base" once the load is in the air.
-Jim

 

[csr0831]

Jim...

Gin poles would be the correct term I do believe. For the purposes of illistration, I showed them to be on level ground. That will not be true in all cases. Most of the time they will be on fairly level grass covered firm dirt. The soil is not so compacted that the poles won't "dig in" once the load is applied, but there are other cases where the ground will be uneven and in those cases I will need to secure the poles and level the suface. For those, I will probably put in a screw anchor and attach the bottom of the poles to them so they can't shift. Good point...thank you for your comment. My main concern is wheather the 4x4's will take the load without breaking given the applied criteria. I'm pretty sure they will be fine, but I am not a structural/mechanical guy.

 

[dfkrug]

The center of gravity WILL be outside the pyramid, but the third "leg" is actually a peice of stainless steel cable that will be tied back to an anchor...this will allow me to control the angle of the other two legs which will extend beyond the bulkhead slightly.

My mistake....you are using 2 legs instead of a tripod of 3 legs. Looks
like it will work.

 

[Shield Arc]

What kind of pump do you have for the jetting? What kind of soil do you have? You do understand a jet doesn't work well in clay, now in sand a jet will cut like a hot knife through butter. :laughing:

 

[csr0831]

I will be using a very old SCOT 1.5 inch circulating pump. It will develop about 55psi and deliver about 80 gal/minute @ 3500 rpm. It was used about 30 years ago to jet down some sheeting in the same type soil. I'll have to jet through about 2 feet of silt/mud, then its all sand. I'll have to be careful of the original piling I am putting it next to...to make sure I do not dislodge it.

 

[smiley]

By the sounds of your project and depending on the terrain, I'd just hire somebody with an excavator with long enough reach, dig a starter hole, chain them to the bucket and swing them into place. Once started, setting the open bucket on top would help in jetting them in.
If this won't work in your situation, you might check my post on "temporary cheap gin pole" just down this page. It sounds like it might be the perfect tool for your project. Set it at the center/edge of your job, make the boom long enough to reach your furtherest piling, cable the sides and back and start swingin the pilings into place. Simple and cheap.

 

[csr0831]

I thought about that, but the excvator won't work and the piles are going to spaced out over approximatly a 200' liniear run, so the gin pole will have to be moved from time to time. Given the fact I can't get any heavy equiment back there, this seemed likethe simplest way to do it. This stuff jetts pretty easy and I suspect the weight of the pole will take it down for the most part.

 

[smiley]

Yep,
I guess it would be tough to find a 100 foot boom and even tougher to find a way to support it!!
I was thinking along the lines of dock pilings that would be stretched out 30-40 ft.