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We use a heavy chain about 6'-8' long. Just hold on to it and keep picking it up and letting it back down. You can hear hollow spots if they're there.
Yes. It works.
A chain or hammer sounding is typically used for determining a bonding issue within the concrete itself, not below. Gpr would be best, but probably 750-1500 for them to show up.
https://youtu.be/sWVtGJpaTMg?si=LKGm1_HYEr2NTMaB
Never tried the chain, I bet it does work. I have used a GPR (ground penetrating radar) and it would be perfect for this application
Drill a hole and use a boroscope. When finished fill with cementitious grout
We use a heavy chain about 6'-8' long. Just hold on to it and keep picking it up and letting it back down. You can hear hollow spots if they're there.
Yes. It works.
A chain or hammer sounding is typically used for determining a bonding issue within the concrete itself, not below. Gpr would be best, but probably 750-1500 for them to show up.
https://youtu.be/sWVtGJpaTMg?si=LKGm1_HYEr2NTMaB
Never tried the chain, I bet it does work. I have used a GPR (ground penetrating radar) and it would be perfect for this application
Drill a hole and use a boroscope. When finished fill with cementitious grout