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capt jim
06-06-2008, 09:05 AM
I would like to remove three dock pilings...approximately 12 inches in diameter...but they must be cut off at the bottom of the canal....in approx' four feet of water...at low tide. Hiring a crane on a barge to pull them out is simply much too expensive. Any thoughts on this problem?

Duffy
06-06-2008, 09:15 AM
I am sure that there will be all sorts of good suggestions posted. In only four feet of water, why not use a handraulic bow saw? I think you can still by them-they were called Swede saws or pulp cutters. A four footer and a couple of spare blades, (they have hardened teeth now,) should cost about $30.00. Better yet, there have got to be some hanging in the rafters of garages around town.

wierdscience
06-06-2008, 09:18 AM
A steel tri-pod with pads on the feet and a 3-5ton chain hoist.Apply tension,all the hoist can manage and let it sit.Check it daily adding tension as it allows.A large turnbuckle could be used inplace of the hoist as well.

A friend and I removed six 8" piles this way,his were in only 6' deep so the hoist alone did the trick.If they were deeper a high pressure pump and wand would be needed to wash down around the pile at the same time it was being pulled.

Ohio Farmer
06-06-2008, 09:18 AM
I guess being underwater rules out electric chainsaws :D How far away from the bank are they? Could ya hook something big to them via a chain (a big one)and pull them over sideways until they either break or pull out? You'll need something big ie dumptruck, 4wd 150 hp+ tractor,dozer with a winch. Good luck !

Al Messer
06-06-2008, 09:18 AM
Our local power company uses hydraulic chain saws on thier bucket trucks. Check with the tool rental plces around you. If nothing else, contact the Army Corps of Engineers if it is a navigation hazzard.

Frederick Harvie
06-06-2008, 09:19 AM
Underwater chainsaws do exsist in both air and hydraulic drives. Stanley tools makes a hydralic one. They can be found on ebay see 370052397858 for a current listing) although pricy for a one time use. You might be able to rent one through a local dive shop or You might hire a comercial diving company for an hour or two to do the job for you

rmack898
06-06-2008, 09:46 AM
A couple of plastic 55 gal drums chained off to the pilings at the water level at low tide, wait till high tide and use a garden hose hooked to a long section of pipe to help "Jet" the piling out. If you have enough of a tidal change, and the poles are not too deep, they should come right out. If you cut them off, the remaining submerged obstruction will ruin someone's day at some point in the future.

oldtiffie
06-06-2008, 10:00 AM
Have a word with some ex-Navy Clearance Divers. They should be able to do it - perhaps even to "blow" them (with "Coretex").

That sort of stuff is what they are trained for. A "passing-out/qualifying" test here in OZ - years ago - was for them cut a railway line in half with a manual/ordinary hardware Store hack-saw!! Under water!!. They - or at least some - were the under-water/diver version of Special Forces and were 150%+ fit!!.

Many Harbour/Port/Wharf etc. maintenance contractors have divers specifically trained for this sort of work.

gellfex
06-06-2008, 10:22 AM
A couple of plastic 55 gal drums chained off to the pilings at the water level at low tide, wait till high tide and use a garden hose hooked to a long section of pipe to help "Jet" the piling out. If you have enough of a tidal change, and the poles are not too deep, they should come right out. If you cut them off, the remaining submerged obstruction will ruin someone's day at some point in the future.

+1. Piles get pulled out all the time by ice and tide.

ahidley
06-06-2008, 10:43 AM
Why wouldnt a gas chain saw work underwater? Get some hose , like a hair dryer hose, and connect it to the air intake and make some kind of fuel filler cap with a hose going to the hair dryer hose. Your only cutting 4 posts, it only has to run about 5 mins.
I would bet that the ignition is water tight. At least moto cross motor cycles are and its the same thing.
Or you can spend the $1K for the underwater version

x39
06-06-2008, 11:21 AM
Years ago I worked for an outfit that specialized in underwater blasting and salvage work ( I was just a deckhand). They had a couple of all stainless hydraulically driven saws that had parallel reciprocating blades. I can only recall them being used a few times. Usually we jetted pilings when they needed to be removed. There was a pretty big pump on the boat that provided water through a pipe that was run alongside the piling and into the seabed. A line from a boom was tied around the top of the piling, and enough strain was taken that the boat would heal a bit, jetting commenced, and out came the piling.

bruto
06-06-2008, 11:43 AM
Why wouldnt a gas chain saw work underwater? Get some hose , like a hair dryer hose, and connect it to the air intake and make some kind of fuel filler cap with a hose going to the hair dryer hose. Your only cutting 4 posts, it only has to run about 5 mins.
I would bet that the ignition is water tight. At least moto cross motor cycles are and its the same thing.
Or you can spend the $1K for the underwater versionIt's an interesting thought, but my guess is that even if the ignition is waterproof, and even if you could get the air intake to work at that depth, the sticking point would be the cooling fan. Most motorcycle engines do not have a shrouded cooling system, but chainsaws do, and once underwater, I think the flywheel fan would bog it right down.

But the whole discussion makes me wonder how difficult it would be to rig up a home-brew air or hydraulic saw using a cheap electric as the base. One of these days maybe I'll play with that.

My first vote would be to try floating or lifting them out before sawing them.

Weston Bye
06-06-2008, 12:07 PM
Blow them out hydraulically, where the piling itself becomes the piston. Bore a hole lengthways through the middle of the piling (Home depot & others sells Greenlee 4' extended drill bits for running electrical wiring, weld or bolt on an extension)

Machine up an adapter bung to pound into the hole, connected to a pressure washer pump. The 12" diameter end of the piling becomes a 113 square inch piston. Even 50PSI will cause 5600 pounds of lifting force to be applied. Air or water will begin to leak around the piling eventually, loosening the piling also.

MickeyD
06-06-2008, 01:52 PM
If the bottom is fairly flat and a little soft, this would be fun to try. Chainsaw the pilings off as short as you can at low tide. Get about 20 12' 2"x6"'s and cut them down to 6', bevel the edges, and then using biscuits or dowels make a big wooden barrel without a top or bottom that can be placed over the pilings and then pump out the water. This would make a cofferdam with a dry bottom, and then you could just cut it down with your chainsaw. It would take about $100 worth of wood if you had to buy it new or if you are lucky you may already have it in a scrap pile. Though it would be heavy, you could roll it around, and flipping it up would be pretty simple in the water. If you do this and it goes well, make sure you put the video on youtube. If it does not go well, you might just win $10K on funniest home videos.

ahidley
06-06-2008, 02:43 PM
Well I'm cheap and spend more time than its worth to do something. So if I had a one time deal like that I'd try using a gas powered portable tree trimmer, only turn it upside down and stick it in the water. Ya know one of the 8 or 10 "chain saws that mount on a weed wacker. $150 from ho-d-poo (aint that how the southeererrs prounce it?) Homedepot

PaulF
06-06-2008, 05:28 PM
I've used hydraulic chain saws underwater before.
They are made just for that reason. Contact a large construction company at the nearest port,LA, SF, Seattle etc.
Ask around for a tool rental company they use for these tools. You can usually rent them. Mines also use them.
PaulF

brian Rupnow
06-08-2008, 03:10 PM
I've been thinking about this since reading it last week. Its rather intriguing. If I were going to do that, I would go to Princess Auto (Its Canadian, but I'm sure that there is an American equivalent) and buy one of the high speed low torque hydraulic motors. You would need the bar, chain, and sprocket from a regular chainsaw, but that is all. You wouldn't need a clutch or speed control. I would take a peice of 1/2" or 3/4" aluminum plate and mount the hydraulic motor to one side of it, the chainsaw bar and sprocket to the other side of it, and 'Voila!!-a hydraulic chainsaw. Mount a portable hydraulic pump with gas engine in a boat with a couple of 8 foot flexible lines, hold your breath, and go!!!

doctor demo
06-08-2008, 05:49 PM
Well, I read all the posts so far and if I were in your boat(pun intended) I would use WES1's approach.He is correct about the lifting power , auto shops use air over oil on car hoists that work quite well at about 125 psi shop air. Not to mention it is way up there on the cool meter.
Steve

jdunmyer
06-08-2008, 09:13 PM
I had a Mall 2-man air-powered chainsaw, picture here:

http://www.oldengine.org/members/jdunmyer/sawmill/mar27_21.jpg

Gave it to a friend who had "come into" a gas-powered air compressor. Want me to see if he still has it and wants to part with it?

Charles Lessig
06-09-2008, 07:44 AM
I would like to remove three dock pilings...approximately 12 inches in diameter...but they must be cut off at the bottom of the canal....in approx' four feet of water...at low tide. Hiring a crane on a barge to pull them out is simply much too expensive. Any thoughts on this problem?
How about a saw chain with cables connected to the ends?
Loop it around the pile and pull it back and forth. Get a
team of diligent workers to haul on the cables.

Last week I pulled a small tree trunk out of the ground by
splitting it with wedges and forcing the halves apart with
a porta power hydraulic cylinder. One side broke off and the
other side was weakened. I cracked the other side off
with the cylinder braced against the ground.

Splitting might work if the weakest part is down in the
mud. If the piles are near each other you might work
by forcing them apart or pulling them together to break
them off. Breaking one could weaken the other.
Regards, Charlie

capt jim
06-09-2008, 07:50 PM
I am so glad to have posted this vexing question here. The thoughts that went into this were all good...and when the time comes for me to commit to some kind of a plan of action....it very well may be from the ideas presented here.
For my first pass, it sounds like I may be using the tides and some jetting. I just have to figure up some cheap, robust, and easy float that can be quite firmly attached to a pile.
This will be lots of fun I'm sure.
Thanks very much guys.
Jim

oldtiffie
06-09-2008, 08:29 PM
You should seriously consider hiring Al "Chainsaw" Dunlap.

He was a renowned expert at cutting things down to size when these things were or were about to go "under water".

Al's your man!!!
http://en.wikipedia.org/wiki/Albert_J._Dunlap

Weston Bye
06-09-2008, 09:08 PM
An empty 55 gallon drum, if fully submerged, will displace 55 gallons of water. At 8 lbs per gallon that amounts to 440 lbs of lifting force, max. You might need two or three.

Good luck, keep us posted.

capt jim
06-10-2008, 06:26 AM
Attaching the barrels securely to the piling appears to be a bit of an awkward task. Keeping them tight to the pile will be difficult at best and keeping them firmly in place as the tide rises and pressure increases will be challenging.
For those trying to envision the scenario....The pilings were from an older dock. They are separated by about ten feet, and positioned about 6 or 7 feet out, and parallel to, a concrete sea wall. The top of the sea wall is about 4 to 7 feet above the water...depending of course upon the tide range of that particular day. A normal range, here in s. florida is about 2 or 2.5 feet. The water depth at the piles is about 4 or 5 feet at low tide.
Mulling this over...the boring and pressuring them out is an attractive possibility, although even after cutting them down to water level...accomplishing the boring through maybe 10 or 12 feet of remaining piling is a daunting task.
The hardware, and keeping it plumb while drilling is just about impossible without a tall structure, (vessel) to work from. Hmmmmm, still thinking...!

Swarf&Sparks
06-10-2008, 08:00 AM
Capt Jim,
Use the tide, you don't need much range, just time.

Build a frame to hold, say, 4-6 drums.
A simple clamping mechanism in the middle (chains will do)
At low tide, clamp the frame to the pile and use whatever other methods (compressed air, water) to loosen the pile, as the tide rises.

As the tide falls, drop the chain and repeat.

Been there, done that ;)

capt jim
06-10-2008, 08:13 AM
Oh yeah...Now I understand the procedure OK....but I'll have to go out and find a place where I can borrow some 55 gallon drums and chains to get this thing underway. Oh...just to further complicate the job...at low tide, I see that these pilings have had a 2 inch concrete wrap around them, from the high water line on down, to protect them from the Teredo worms. The worms bore through the wood until it's just about all gone, and make a piling look as though a beaver was at work at it. I guess I'll have to sit out there on my 4' X 4' work platform and do some chipping to get rid of the concrete....oh joy...what fun this is going to be...heh heh.

Swarf&Sparks
06-10-2008, 08:49 AM
Where are you Jim, that T navalis is such a problem?

capt jim
06-10-2008, 09:08 AM
OK, whats T navilis???
Anyway, I am located in beautiful Boca Raton, Florida. South east Florida coast, just a half hour drive north of Fort Lauderdale, or an hour drive north of Miami.
One of the issues here is that all this messy work will be taking place in what it considered to be an upscale residential neighborhood. Oh, I will have lot's of folks watching and wondering what the hell I am up to now....heh heh...and I am usually up to something pretty much all the time. I could be considered the neighborhood entertainment.
For right now, the winds are calm this morning so I am going out to my front yard and fly my radio controlled helicopter....gotta watch out for the cars though...or it could get to be pretty noisy in a real quick hurry...heh heh.
jim

Swarf&Sparks
06-10-2008, 09:28 AM
T, Navalis
teredo navalis, the "shipworm" which you mentioned in an earlier post.
Thank gawd we don't have em here (tho we have our share of marine nasties)

Re the concrete casing, can't you reach with an electric jackhammer at low tide?
What is your tidal range anyway?


Keep the bean-counters guessing, in their flash waterfront appts.

If it wasn't for the likes of ingenious types on this board, they'd still be living in trees, and counting the leaves.

capt jim
06-10-2008, 09:38 AM
Oh...technical worm terms eh.
I'm not real comfortable with electricity while bobbing around on my 4 square foot foam work platform. It's a bit tippy you see....heh heh...and sometimes so am I...bad combination I think.
Bean counters, and doctors, and stock brokers, etc etc. They are amazed that I (am so poor) actually mow my own lawn.
jim

Swarf&Sparks
06-10-2008, 09:42 AM
OK Jim, fair call re the volts, if you're not steady on the platform with an earth fault breaker.
You'll just hafta hire a FB air hammer and compressor, on the weekend, when it's cheap, like sunday morning :D

Weston Bye
06-10-2008, 12:31 PM
Attaching the barrels securely to the piling appears to be a bit of an awkward task. Keeping them tight to the pile will be difficult at best and keeping them firmly in place as the tide rises and pressure increases will be challenging. ...

Three barrels stood on end, bungs up and filled mostly with water. Position them around the piling and run a chain and chain binder around everything, cinched up so that you *start* to deform the barrels. pump out the water and let them work. You might want to add some hunks of angle iron to the piling with lag bolts to hook the edge of the barrels under.



Mulling this over...the boring and pressuring them out is an attractive possibility, although even after cutting them down to water level...accomplishing the boring through maybe 10 or 12 feet of remaining piling is a daunting task...

Ten or twelve feet??? Wow. Forget about drilling. I was thinking maybe 4 or 5' below the bottom.

Mad Machinist
06-10-2008, 01:10 PM
Wish I could get a license to blast in Florida....:D ......bout 12 feet of det cord per piling ...a few sand bags to focus the blast....:D result...lots of pretty bubbles and floating pilings....

dave5605
06-11-2008, 07:38 PM
ok, a real dumb idea. Can't you use a oxy/acetelene torch under water (to cut steel)? If the oxygen can keep the torch lit and get hot enough to cut steel under water is seems that it might just cause the wood to start burning right at the torch tip.

Or how about a air powered drill (will it work underwater?) and drill (butcher) a bunch of horizontal holes into the piling and then hack away at whats left. Use a self feeding auger and drill 6" into it all the way around.

Fasttrack
06-11-2008, 08:14 PM
12" diameter ... 4 foot deep water ... just do it by hand. It won't take that long to cut only three. If I can cut 12" and larger diameter seasoned "hedge" (osage orange) and I'm a pretty skinny fellow, then that shouldn't be horrible.

The other options are more fun, but I bet you'll spend less time doing it by hand than you will doing anything else.

I dunno - I've spent lots of time and money making "tools" to do stuff I could've done by hand so I'm not trying to get up on a soap box or anything.

davidh
06-11-2008, 09:55 PM
Wish I could get a license to blast in Florida....:D ......bout 12 feet of det cord per piling ...a few sand bags to focus the blast....:D result...lots of pretty bubbles and floating pilings....
and enuf fish for the family for the summer/ / /

x39
06-11-2008, 11:25 PM
and enuf fish for the family for the summer/ / /
When I worked the aforementioned job, it was amazing how quickly sea gulls would appear after an underwater explosive shot. There would invariably be a few dead fish floating around, and they were right on the scene to get them. I maintain the best way to get the pilings out is water jetting. Rent a trash pump and rig a piece of pipe to the end of the hose and you're good to go. No muss, no fuss.

bruto
06-12-2008, 12:34 AM
ok, a real dumb idea. Can't you use a oxy/acetelene torch under water (to cut steel)? If the oxygen can keep the torch lit and get hot enough to cut steel under water is seems that it might just cause the wood to start burning right at the torch tip.

Or how about a air powered drill (will it work underwater?) and drill (butcher) a bunch of horizontal holes into the piling and then hack away at whats left. Use a self feeding auger and drill 6" into it all the way around.

Remember that a cutting torch is not really cooking through the steel with heat, but burning it with oxygen. That's a process pretty much limited to ferrous metals. I don't think wood would react the same way, especially when wet, and it would be a long and tedious process if it worked at all.

JRouche
06-12-2008, 01:11 AM
Dunno but it sounds like a job for a professional, thats why they are professionals, they have the tools. Instead of renting a boat, under water breathing apparatus, air saws and insurance they do it for you.

Other than that, you floating around on yer dingy looking at it isnt gonna get much done..

The pilings are encased in concert? How deep? You could be looking at another ten to fifteen feet below ground.

You either cut them off at ground level, which you cant do cause the concrete is above ground level, or you pull them. Are you ready to handle ten feet of encased concrete poll. Even five feet of encased poll, prolly not. Think HEAVY!!!

If the concrete is anything higher than about five feet below the water surface you dont wanna just slice off the wood and leave the concrete post there for future reference...

Nope, theres a lot of weight there, if yer thinking of trying to water jet them up you will still need a real crane to pick them up, cant just leave then on the floor..

Its a crane op, floating or land based.. JR

capt jim
06-12-2008, 07:54 AM
Wow...what an emotional roller coaster ride this thread has turned out to be.
As I read through the ideas being offered, I alternate between euphoria...and depression...heh heh...just kidding, but it sure is being entertaining and educational all along the way. The latest in this saga is the potential for a long delay after applying to the city for a permit to do all this work. This is a city neighborhood, and not much escapes the ever watchful eye of "big-brother".
Total removal of the pilings seems to be the only real answer...since this will be a boat dock again...and perhaps off into the future, a deep keel sailboat could "find" the cut off stump of these old piles... as the vessel descends with the outgoing tide...with some terribly unhappy consequences.
I can stand at the base of these pilings at low tide and wail off the thin concrete shell with a ten pound maul. Then I would be left with a relatively clean pole to jet/float out of the canal bed. Another idea we had was to use the new pilings as a lever...to pull the old ones up, along with jetting of course.
With a fulcrum on the sea wall, I would get about six or seven feet of pole cantilevered out to the old piling....the remaining length of piling lying on shore...maybe 10 or 12 feet...would be a counterbalance...and we can get all our fat friends to sit on this see-saw as may be required. Just a thought so as to make use what materials may be at hand.
Thanks very much to everyone who has contributed their thinking to this thread.
jim.

A.K. Boomer
06-12-2008, 09:31 AM
Lot of good and cool suggestions, What about using the poles against each other, how high up are they from the bottom and how far apart, take a come-a-long out there with some strong rescue rope (spectra) and collapse them into each other? Work two against one and when there's two semi lose work them against the one strong to make it weak then start plucking them out?

capt jim
06-12-2008, 09:46 AM
They are each ten feet apart from the next one, in about four feet of water at low tide...and approx' 12 feet from top to sea bed....with maybe another four feet into the sea bed.

Swarf&Sparks
06-12-2008, 09:51 AM
All the more reason to use drums.
Lift em out, float em and tow em away :D

A.K. Boomer
06-12-2008, 10:03 AM
Then You have extreme control over them, it might be worthwhile to give it a go,
What I try to do when doing something oddball is start simple and then step it up as needed, A come-along and some good quality rope or even cable is about as simple as your going to get, you can also rig things so you can create extreme leverage against the posts by mounting as high as you can go and also wrapping around and then end anchoring in the middle of a line thats already ran between two posts, this will increase vector loads and give you manipulation abilities ------- So before you go dragging out the 55 gallon drums and getting the "authorities" involved it might be worth a try,
One note; You run the risk of snapping a pole off at an inappropriate level, But you also have so much control that you would have to be very "gun hoe" to do so, cinch up and and inspect/measure-repeat-repeat-repeat.

Swarf&Sparks
06-12-2008, 10:09 AM
I'd agree with the come-along etc, if you could pull from overhead.

Mates and myself built a barge for the local yacht club to do this sorta work (laying and lifting moorings, 2 ton of concrete, plus a ton of chain/shackle/swivels/etc)

But, as you say, you stand a good chance of breaking a pile in the wrong place.

It's a lot easier to back out a tap, than try to remove a broken one ;)

A.K. Boomer
06-12-2008, 10:16 AM
Thats what the measurements are for, go a little then back off and measure, If you budged the post then it will be closer, If your just springing the wood then it will bounce back to the same measurement;)

Swarf&Sparks
06-12-2008, 10:23 AM
Agreed, we'd have to be on-site to see what's really happening.

A.K. Boomer
06-12-2008, 11:16 AM
Yes a picture would be worth a thousand words, but if i had to show up with the info that I have this is what I would bring -- a good come-along -- some cable and u-clamps or bombproof low-shock spectra rescue rope (or both) One rope/cable pulley,
A level with a hefty V-grove (for vert. measurement to verify which post you budged)
Some cheap plastic notebook covers (Rope/cable friction reducers that can be wrapped around different poles for manipulation of others)

He didnt give the poles configurations, to me the worst could prove to be in line if the sea floor is really solid , although it would be the bomb for putting two poles against one the end poles cannot be Wiggled in other directions while the middle would be cake, if the poles are making up a triangle then you can do wonderful things to all of them even in some very firm seabed.

But in-line does have one advantage as it can be manipulated in another vector of attack, by anchoring high in the middle and using one dead end at the bottom of one end pole and keep the other active but anchored at the bottom of it you now have more than a 45 degree angle (poles are 12' tall and 10' apart) and are pulling the one end pole "up and out" -- but dont go all the way, you have to swap your rigging around and use it as a low anchor to loosen the other end pole first, But dont pluck the other totally out, now all rigging must be reversed with the anchor ends high on both end posts and the middle post low and pulley'd , in fact depending on the ground this all might have to start from reverse and the middle loosened first, In line could prove to be a pain in the arss, but Id do it rather than have to pay someone, thats how you learn, You might even learn you have to pay someone:p So be it -- your still learning.

Swarf&Sparks
06-12-2008, 11:28 AM
I know what you're saying bro.
Can you imagine all those bean-counters and ad execs watching us?
:eek:

A.K. Boomer
06-12-2008, 01:45 PM
They hate guys like us Swarf, they just hate us:)
we simply cannot be "tallied up" into a predictable form of any kind of projection sales analysis. i think its safe to say were off the graph.

Oh yeah, I would bring a roll of duct tape also:)

Swarf&Sparks
06-12-2008, 01:48 PM
I know it as gaffer tape but, yup, that and a lil bottle of loctite 406 :D

dave5605
06-13-2008, 05:50 PM
Got a bunch of 4 wheeler/offroad friends with winches on their trucks? If you can get close enough, hook 3 or 4 winches to the post as low as you can (so it won't break as easily) and try to winch it out.

If you get the trucks or guys riding on the new pilings as a lever be sure to take some pictures. 4 trucks/winches, 6 'fat guys', new pilings, couple of cases of beer and you should be able to sell tickets to watch the 'show'

With 12' sticking out and only 4' in the ground they might come out pretty easy if they don't break off.

comdiver
12-20-2009, 08:46 AM
When I worked as a comerical diver we used hydraulic chain saws. I did one job where we had a lot of pilings to cut. It went really well until I found the one made out of steel. Ultrathermic cutting would also work "Broco Rods",
these are a steel tube filled with magnezium wires. You apply electrical current to the rod and arc it to metal to cause the rods to burn ad the blow o2 through it to burn through. To use either the saw or the burning rig you should be traned as a comerical diver. Try pulling from shore, floats or jetting.
If there is a fire hydrant nearby that may give the water needed. You would need a hose with a pipe to blow the water along side the pile.

Black_Moons
12-20-2009, 09:10 AM
comdiver: You sure seem to be an expert at digging up old things.

HSS
12-20-2009, 09:49 AM
I guess those old pilings are still there, he never came back to this thread to say he got them out.:D

comdiver
12-20-2009, 09:58 AM
I didn't realize how old the thread was. They must be rotted out by now.

airsmith282
12-20-2009, 10:00 AM
use and AIR Powered Sawsall problem solved

have a good day

Robo
12-20-2009, 12:53 PM
I would like to remove three dock pilings...approximately 12 inches in diameter...but they must be cut off at the bottom of the canal....in approx' four feet of water...at low tide. Hiring a crane on a barge to pull them out is simply much too expensive. Any thoughts on this problem?

Stanley bostitch makes a hydraulic driven diamond tipped chain saw that I think would do the trick. We use them to cut water mains etc.

darryl
12-20-2009, 01:52 PM
encased in concrete- sounds to me like you'll have to be able to wrap a chain around the lowest available part of each piling, then cinch it up tight before you could apply flotation forces to it.

You're basically trying to pull them upwards- if you can pull on a cable from shore, why not use some leverage- if you leaned a post of sorts against the pile at a bit of an angle on the shore side of the piling, you could pull straight sideways towards shore and be giving the piling an upwards pull. The post you use would need to have a base so it could apply force to the bottom without sinking in, and the top of the post would have to lean into a notch in the piling so it wouldn't just slide up as the cable pulls. Cinch the cable around the piling right at the point where the notch is cut for the post to lay into. The top of the post would have to have a flat area to lift with- if it was just a pipe it would simply punch its way into the piling without giving much lifting force.

If there was any way to make that leaverage post extendable in place, that would make it a lot easier to work with. Place the post, crank it up, which will make the piling want to lean away from shore, then pull with the cable. Re-adjust the length of the post as required and pull again.

Off the top, I'm thinking at leaning the jacking post at about a 25-30 degree angle would be about right.

The only technical stuff being done underwater is placing the bottom of the jacking post. Once you have the piling out, you've already got a cable attached to bring it to shore and handle it from there. Any idea how heavy it's going to be, especially concrete clad?

mark42
12-20-2009, 03:38 PM
I worked as a diver and have used the hyd chainsaw. Not easy work and I always wore kevlair