Concrete X-Ray?

[dgbldr]

It is my understanding that there are specialized contractors with equipment that can "see" inside of concrete slabs and locate rebar, various voids and other conditions, etc.

I am curious as to the real-life (not advertised) capabilities of such equipment, specifically the ability to locate pipes and/or pipe leaks fairly accurately.

If you used such services, kindly give me some feedback.

[Scott Jameson]

Re: Concrete X-Ray?

Successfully locate post-tension cables before cutting into monolithic fnd/slab with surveyor's help. They use powerful/accurate "metal detectors" to locate buried property markers.
Doubt it works for non-metallic locates.

[dgbldr]

Re: Concrete X-Ray?

Thanks. I have used a service that can do that. They hook up a radio transmitter to the accessible end of the pipe/cable and trace it with a receiver.

I need to "look" into a slab where I have a surface wet spot but don't know if a pipe is under there and leaking, or what the source of the water is. If there is a pipe in there, it would be Cu, as all piping in the building is Cu.

[MarkMc]

Re: Concrete X-Ray?

Should be able to detect copper with metal detect or high freq tracer. What your seem to want is GPR.

[e hilton]

Re: Concrete X-Ray?

I have used GPR to locate old fuel oil tanks, but the image requires a specialist to interpret. It's not even close to the medical xrays you are familiar with, it's more of seeing "areas of interest" that show as different densities. many years ago we used xrays to find steel in a concrete floor slab, but it was an office floor that we could get access to top and bottom. If you have a slab on grade, you're going to have a difficult time puting the xray film on the bottom side of the slab. Maybe some kind of ultrasound equipment? If they can tell the gender of a baby maybe they can find a copper pipe.

[Dick Seibert]

Re: Concrete X-Ray?

Maybe some kind of ultrasound equipment? If they can tell the gender of a baby maybe they can find a copper pipe.

Our Special Inspectors use portable ultrasound machines to document all welds now, call a Special Inspection firm in your area and see what they say.

[MarkMc]

Re: Concrete X-Ray?

I have used GPR to locate old fuel oil tanks, but the image requires a specialist to interpret.

He's not going to run an x-ray device or ultrasonic imager himself either so like the 'problem' the solution needs interpretation (by trained operator) too, and of course budget issues laid out otherwise a skilled GPR operator can cover can cover ~16^ft in about 1/2 hr incl interpretation.

[dgbldr]

Re: Concrete X-Ray?

After further review...

GPR people tell me they can locate a pipe but cannot determine if it's leaking.

Regular radio-locating requires electrical connection to the pipe in question, at some accessible point. That's a problem, as I don't know if there is a pipe there, let alone which pipe. This is a commercial building with lots of pipes...

To complicate things, location company tells me this year they've had an unusual amount of slab puddles that turned out to be ground water, not pipe leaks. Apparently due to the unusually cold winter and rainy spring.

Looks like we may be looking at some expensive hit-and-miss work.

[MarkMc]

Re: Concrete X-Ray?

You should be careful with the liberal use of "we" there.

Again details rule. Locate and listen (use your good ear though).