Replacing underground water pipe below concrete

[Pennine Ploughing]

Got 10 meters of galvanised pipe that has burst under concrete, can dig a pit in either side, just was thinking of pulling old pipe out at one end with new pipe connected to old pipe, so new pipe is pulled in behind old pipe.
Has anyone done this before and any advice on how to do it ?
Would it be possible to push a wire rope through pipe and connected to an expander as its pulled out, or what options is there other than digging up the concrete.

Tia

 

[Cab-over Pete]

One of those mole things? Pushes its way through the land. I think they can change direction and all sorts with them.

 

[Dry Rot]

How big is the steel pipe? Could you insert the new pipe inside the old pipe? (Thinking of doing that here with redundant 2" asbestos cement main, just never got around to it!).

Your idea would work and work even better if you could put water through the new pipe at the same time. Not at great pressure but enough to lubricate the process. Like they do when inserting a catheter! (Probably won't need the anaesthetic though).

 

[Lazy Sod]

I've pushed a 15mm blue poly pipe up a 1.25" iron pipe in the past. Easy to do.

 

[Chickcatcher]

Got 10 meters of galvanised pipe that has burst under concrete, can dig a pit in either side, just was thinking of pulling old pipe out at one end with new pipe connected to old pipe, so new pipe is pulled in behind old pipe.
Has anyone done this before and any advice on how to do it ?
Would it be possible to push a wire rope through pipe and connected to an expander as its pulled out, or what options is there other than digging up the concrete.

Tia

I cant imagine my suggestion will work but how about putting a cable on the back just in case the one you are pulling with breaks and you may just be able to retrieve it

 

[Flatlander]

here they can push pipe for a few hundred meters and guide it perfectly to a water trough. Not sure how but it’s pretty common. Unless a larger diameter pipe is needed pass a piece of multi strand cable thru the attach new one to it and pull it thru. Good chance the inside diameter could be less in places from corrosion

 

[Pan mixer]

Corrosion in an old metal pipe will cut down the diameter so much that pushing plastic through it would be useless.

Try and pull the old pipe out and the new one in the same movement? The chaps who put a pipe under a road for me had a good gadget that fastened the new pipe onto the rope that they had pulled through the hole when retrieving their mole.

Alternatively get one of those type of companies to come along and push a mole through the soli next to the old pipe, they only need a smallish hole - about 6 feet long and just deeper than the pipe) at one end to operate.

I had a similar length one under a road and it cost me 750 and took a couple of hours - much cheaper than breaking concrete or going round the slab I would suggest.

They are quite keen to know that they aren't going to hit anything else on their mole journey though - drians, water mains, gas pipes etc.

 

[Exfarmer]

I would get a steel step up connector to a larger size then step down again to the plastic, if you see what. I mean. Of course you are certain their is no tee in the galvanised!

 

[Wisconsonian]

10 meters, use a piece of plastic pipe that will go OVER your pipe 5 meters long, hook that up to water, plug the original pipe and jet around the outside of the pipe, in 5 meters from each end. pull the old pipe out by hand, push the new one in by hand.

Or you could try to pull it in one shot with or without a cable through the middle to be able to pull out a piece that breaks in the middle, but if it starts to move, it will probably make it all the way without breaking off. If it's going to break, it will break when it's locked in place.

 

[Steevo]

One of those mole things? Pushes its way through the land. I think they can change direction and all sorts with them.

Exactly this - impact mole would work well on a job like that and be very cost effective.

 

[Pennine Ploughing]

Thanks for the replies so far,
Moling men won't touch it, 2 reasons, there is an underground electric cable, and a gas pipe, also a sewer pipe, this is from a house to the boundary, united utilities don't seen that helpful as its not their pipe, and wont even detect the underground services in case they get it wrong, owner not really wanting the concrete all dug up,
It was just a thought that pulling new pipe in by pulling old pipe out,
We are thinking clean water feed to house will be the deepest service in there.
10 meters distance would be
The bit under the concrete

 

[Exfarmer]

Thanks for the replies so far,
Moling men won't touch it, 2 reasons, there is an underground electric cable, and a gas pipe, also a sewer pipe, this is from a house to the boundary, united utilities don't seen that helpful as its not their pipe, and wont even detect the underground services in case they get it wrong, owner not really wanting the concrete all dug up,
It was just a thought that pulling new pipe in by pulling old pipe out,
We are thinking clean water feed to house will be the deepest service in there.
10 meters distance would be
The bit under the concrete

If the pipe is large enough I would try feeding a pipe through with all those services. If necessary reaming the pipe first.otherwise I can see no reason not to just pull it through with the old pipe.

 

[Wellpark]

How big is the galv pipe and how big alkathene do you want to put in ?

 

[Pennine Ploughing]

How big is the galv pipe and how big alkathene do you want to put in ?

Wanted 25mm new pipe, not sure what old ones is, think it's 3/4",
Was hoping the rust on outside of old pipe would hold a bit of soil to it and make a bigger hole than it is, to pull new through with it

 

[michael N123]

It won’t take much concrete atall if you stihl saw and peck out a strip to lay a new pipe in… no need to rip the lot up just ignore the old pipe

 

[Oliveau]

It won’t take much concrete atall if you stihl saw and peck out a strip to lay a new pipe in… no need to rip the lot up just ignore the old pipe

I’d go with that - open cut let’s you clear anything that might be there. Put your pipe in a duct then backfill with foamed concrete.
Who actually owns the road?

 

[Speedstar]

We did one the same wire rope throw the old pipe & pull the old one out then put a hose off the power washer throw the hole cleaned it out nice then used a compressor to blow a rope throw the hole to pull the new pipe throw with it worked well, old pipe took some pulling out , we used a 12 mm wire rope with a clamp on the end to pull it out

 

[Wellpark]

If you can get a wire rope through the pipe after it is through untwist a bit about a metre from the end and put a small stone in middle of rope to swell it bigger than new pipe and then fasten new pipe over wire rope and pull rope taking old pipe out and new one in in one go

 

[organicguy]

My experience of trying to do similar is that you will not pull the old pipe out. If it has rusted enough to leak it will be too weak to pull out without breaking.
If no one will mole your only hope is to break out the old pipe with a mole and pull a new one in at the same time.
It is relatively easy to push a new piece of scaffold pole in compared to pulling out a rusty old pipe.

 

[Brains]

Could you slide some say 3” steel tube over the old pipe and bang it thought while using a pressure washer with a long pipe and a straight nozzel to soften the soil at the face?