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LOU'S CUE'S
01-11-2007, 01:40 AM
a friend is bidding a job cutting 12" steel pipe, filled with concrete & 4ea. 3/4" rebar. there are 106 of these pilings.. need to be cut off at riverbottom in about 12 feet of water. these are like 80' long !!

(another contractor had tried a hydro piling puller & water jet would not move them.)

soooooooo...this friend has barges, excavators, crane, etc. he's thinking of renting a hydro saw that would connect to the end of his excavator, and sawing them off. he has used this type of saw in the past and says it will work.

i think some type of donut shaped-charge....thermite ??? or?? would be a LOT COOLER !!! he hires divers & demo contractors on a somewhat regular basis.

any ideas ??

this group is a GREAT source for all kinna neat ideas & info......thanks to all !!

thistle
01-11-2007, 07:04 AM
try mar- vel in philly- they have stuff for under water cutting

www.mar-vel.com

thistle
01-11-2007, 07:47 AM
http://www.mar-vel.com/pdffiles/P090_092_CUTTING_WELDING_05.pdf

thistle
01-11-2007, 07:53 AM
of course you could have a go with a shaped cutting charge , but it would probably be easier to go and burn each piling off and then lift it out one at a time .

Evan
01-11-2007, 08:19 AM
Use a chainsaw.

http://www.steffeninc.com/htm/cs06.htm

Nevermind. I haven't had coffee yet. Try primacord.

http://www.norabel.com/products/otherproducts/

neonman
01-11-2007, 08:58 AM
If these pilings are 80' tall, why can't one tie a heavy cable to the top of the piling, and have a big bull dozer just pull them out one by one?

neonman

EDMTech
01-11-2007, 10:08 AM
Why a shaped charge? Way too controlled and unentertaining. Bore a 6" hole in them, fill them with high explosive, and have a contest to see how high I could shoot them out of the water :D

motomoron
01-11-2007, 10:31 AM
Solicit quotations from companies that actually do this sort of work, and who are unaware of this job. Pick the a vendor for the service. Add a hefty % to that number, and bill the people with the piling problem that amount.

Subcontract the removal and disposal.

Any time you can subcontract a job, and make more money with the time you save in the process, you've done well.

gundog
01-11-2007, 10:53 AM
I would think some kind of hydraulic cutoff saw would work pillings held by a crane. We used to have a bracket that bolted to a pole and held a chainsaw it pivoted so the saw was held when the pole was cut off. I would think you could make something up that would work the same. Use a hydraulic motor attched to an arbor with a cutoff blade that can cut steel and concrete mount it on a bracket that can be clamped to the pilling. I would think this could be done fairly cheap.
GD

bhjones
01-11-2007, 12:14 PM
Oxy arc cutting will cut both the steel and the concrete if he wants to send in divers. Your buddy should be looking at diving contractor subs for this job.

Evan
01-11-2007, 12:18 PM
Really, for a job like this linear shaped charges are the way to go. The water is really shallow so divings costs will be minimal. No tanks needed, just a simple hose hat and air compressor. Linear shaped charges will be easy to set up. You shouldn't have any problem finding somebody to do the work near a big river.

Oh yeah, make sure you get a permit from the fish warden.

winchman
01-11-2007, 03:43 PM
The steel tube and concrete probably won't be a problem for the shape charge, but what about those pesky rebars? How far are they from the center of the piling?

How much of the 80' length is above the bottom of the river?

Roger

Evan
01-11-2007, 03:49 PM
Just wrap an extra loop of charge around it for the rebar. Explosives are relatively cheap. The costly part will be the crane and operator.

pressurerelief
01-11-2007, 03:56 PM
Take a look at Billy Poe. His company is
Explosive Services International
1214 North Cicero Avenue, Baton Rouge, LA 70816
(225) 275-2152

He does all the vent and burns for all of the class A railroads in the US. Believe me, there is nothing like watching 23,000 gallons of liquid propane go up in one big ball of thermal destruction.

Seriously, this is right up his alley, has the credentials, experience, licenses, and knows how to talk to the Coast Guard. He does alot of the work off Lousiana in the Gulf oil fields.

Mike Burdick
01-11-2007, 04:50 PM
Twelve feet of water, huh...

Okay he has barges and cranes. Make a round steel tube about 7- feet in diameter and 16-feet tall that can be split in half. Then put that around the piling, bolt the two halves together and then drive it in the river bottom about a foot or so. This shell will give a person 3-feet of working room around the piling.

Get a good pump and remove the water and to keep any leakage out. Cut piling, concrete and rebar with an abrasive saw no diver or special equipment needed. Then pack up, clean up, remove shell, and move to the next one.

By this method he can minimize polluting the river with mud, concrete, and steel cuttings - something he will no doubt be required to do.

Typically sheet piling is used for this but since he has so many to do the shell might be easier.

bhjones
01-11-2007, 05:01 PM
No tanks needed, just a simple hose hat and air compressor.

State and Fed Regs play into what's required for the job, as do company S.O.P.s, but I find this statement amusing.

A simple open circuit system is simple and cheap, even with true redundancy built it.

A surface air system is specialized from top to bottom. You have Compressor system sized to supply the working diver(s) and the backup team (big CFM), the filtration system to clean the air of oil and other impurities, Special hose that is breathing air safe, communications cables, etc, etc wrapped in the umbilical. The diver then needs his end of the air delivery system (superlite 17 or whatever), and communications, his bailout scuba system and the hundreds other details I've missed.

Since you'd have people working with the diver on the surface (crane operator) your going to need to have communications at a minimum so your going to have a tethered diver.

All that said, if I were in the water on this one I'd have serious trust issues with any crane operator holding up a few tons of steel and concrete over my head while I oxy-arc'd through the thing. Using explosives to sever the piles would sound pretty good to me.

bhjones
01-11-2007, 05:07 PM
Who in their right mind would crawl into that death trap? Good luck sealing the split in the casing. If he has a crane why cut it in the first place.


Twelve feet of water, huh...

Okay he has barges and cranes. Make a round steel tube about 7- feet in diameter and 16-feet tall that can be split in half. Then put that around the piling, bolt the two halves together and then drive it in the river bottom about a foot or so. This shell will give a person 3-feet of working room around the piling.


Get a good pump and remove the water and to keep any leakage out. Cut piling, concrete and rebar with an abrasive saw no diver or special equipment needed. Then pack up, clean up, and move to the next one.

By this method he can minimize polluting the river with mud, concrete, and steel cuttings - something he will no doubt be required to do.

thistle
01-11-2007, 05:11 PM
I would dive on it, cut the tube to weaken the piling, flop the piling over then sever exposed rebar.

pressurerelief
01-11-2007, 06:48 PM
If you want to do this for real all kinds of standards have to be followed. Diving headfirst into a piece of pipe secured around these is not the answer. Take a look at, 29 CFR 1910.146 (Confined Space Standard), and 29 CFR 1910.134 (Respiratory Protection).

Even by following standards such as these, the company I use to work for averaged a death about every two years. The sad part is, this company is the largest in the nation at what they do and has a full time safety division with lots of personnel. They had procedures on how to wipe your backside and still people got into trouble.

Good Luck, Be Safe!

gundog
01-11-2007, 07:17 PM
Here is another thought cut them off at or slightly above water level use a pile driver and drive them in flush with the bottom.
GD

Evan
01-11-2007, 07:31 PM
but I find this statement amusing.

I wasn't recommending that somebody go to HF and buy a cheap compressor and a plastic bag over their head. Shallow water diving doesn't require the same equipment the deeper water does though. Bailout scuba? In 12 feet of water?

Fasttrack
01-11-2007, 07:50 PM
"Oxy arc cutting will cut both the steel and the concrete if he wants to send in divers. Your buddy should be looking at diving contractor subs for this job."



I kinda remember Hoffman saying that a while back. Thats pretty cool and seems like an easy/quick and safe way (if you only have to do one or two at most) to do it for one or two pilings, but 80? In my mind, the more times you go under, the greater your chances of not coming back up...

bhjones
01-12-2007, 12:00 AM
6 feet, 12 feet, 150 feet. It's all the same when the air stops flowing down the umbilical. By amusing I only meant it gave me a chuckle. No offense intended.


I wasn't recommending that somebody go to HF and buy a cheap compressor and a plastic bag over their head. Shallow water diving doesn't require the same equipment the deeper water does though. Bailout scuba? In 12 feet of water?

bhjones
01-12-2007, 12:03 AM
Most piles are driven until they hit hard stuff. It might not be possible.


Here is another thought cut them off at or slightly above water level use a pile driver and drive them in flush with the bottom.
GD

thistle
01-12-2007, 07:41 AM
why not knock them clean through to china ?

dicks42000
01-12-2007, 07:48 AM
Well, assuming the piles are aimed in the general direction of China, it's a long drive....(Oh no I sound like Cliff Claven !)
Anyway, then the Chinese can break up the used pilings with hammers & torches, make gravel out of the crushed concrete & send the steel & rebar back to N. America as cheap bandsaws & those dreadful pressed steel stands for equipment, that Grizzley, Busy Bee, Harbour Freight, etc. sell.

GKman
01-12-2007, 12:36 PM
I'm disapointed in you rednecks. Just tie a CHI-COM, NO-GOOD, JOB-STEALIN', Harbor Freight JUNK-B****RD vertical mill to them and let it shake 'em out! :)

Evan
01-12-2007, 12:45 PM
A small tactical nuke will remove them quickly. Deepen the channel too.