Is There Such A Thing As A Concrete Detector ?

[Old_Geezer]

Finding a lot more slabs under my lawn than I imagined were there. I'd like to find and expose them all, perhaps to remove them, but unless it's showing at least a bit of exposed face, it's difficult to know where these "stepping stones" are located. It'll all be guesswork and digging over the whole thing. (Did try pushing a fork into the lawn, but it's all dry clay and I just end up expending time & energy in the wrong place.) I know metal detectors exist but is there anything (cheap) that can look under the surface and detect the dense concrete apart from thick clay ?

TIA

[wolf63]

to find buried bodies they use ground penetrating radar, maybe you could rent a machine.

[Old_Geezer]

You make a good point. If I can spread a rumour that there's a dead body under there somewhere, maybe the police will come around and find them all for me !

[bobbinwales]

Can you find a long thin metal spike.... you should be able to hammer that down fairly eay through clay and youd know if you hit concrete (or if its a stone just move along abit and try again)

[Old_Geezer]

A possibility, thanks, but except where I've dug previously and sieved the stones out, there are a lot of them to hit. And I'm not keen on cracking a slab if one's there. Even if I end up removing them, they'd be useful elsewhere. I'd prefer to use waves/echoes/whatever to find them, if possible.

[Buenchico]

To the best of my knowledge, the only thing that could reliably do what you want is ground penetrating radar. As has been suggested, it's possible to rent a GPR machine but the minimum rental period is usually one week, with prices starting from £250 (but with £350 being closer to the norm). So it's far from cheap!

[Peter Pedant]

yeah you would be able to do it with ground penetrating radar easy
( so yes the technology exists)

and I dont want to pay more than a ham sangwich!
yeah OK forget the ground penetrating radar....

[Peter Pedant]

yeah like bobo
one of those prodders they use to find bodies on peat moors etc

[douglas9401]

You could just wait for the inevitable rain then use the fork.

[DTCwordfan]

OG - your thread reminds me of this old one:

An old man lived alone in the Zimmerset countryside.

One spring, he wanted to dig his tomato garden but it was very hard work as the ground was hard. His only son, Barnie, who used to help him, was in prison. The old man wrote a letter to his son and described his predicament.

Dear Barnie – I am feeling pretty bad because it looks like I won’t be able to plant my tomato garden this year. I am getting too old to be digging up a garden plot. If you were here, my troubles would be over. I know you would dig the garden for me. Love, your Papa.

A few days later he received a letter from his son…

Dear Papa – I’d do anything for you Papa, except dig up that garden. That’s where I buried the bodies. Love, Barnie

At 4 o’clock the next morning, Inspector Morse, the CID and local police arrived and dug up the entire back-garden without finding any bodies.

They apologised to the old man and left. The same day the old man received another letter from his son.

Dear Papa – Go ahead and plant the tomatoes now. That’s the best I could do under the circumstances. Love, Barnie

[jno]

ha, very good, DTC

[Old_Geezer]

:-)

Yeah, there's a limit on what it's worth. Pity there's no simple circuit one could put together to do the job.

Exposed about half a dozen today before stopping. Have to see what I finally end up with.

[jno]

have you asked English Heritage? It may turn out to be Roman remains, or at the very least an important example of brutalist flooring.

[Old_Geezer]

Unfortunately the ones uncovered were not. Basic squares & hexagons. I think I'll just have to forget detectors and just try to find what I can.

[Tuvok]

Could you guess the route they would have taken?

[douglas9401]

I have a few more vague suggestions, nothing concrete though.

[Old_Geezer]

Many seem random but there does seem to be a "path" of them up the middle; however that has already caused me to look in a place which doesn't seem to have one. If I can uncover the middle lot they would likely stay although I may re-lay them to be a bit higher.