Which equipment used to measure sound passing through the concrete?

dB meter

Concrete is primarily a sound insulator rather than a conductor. So, there’s hardly any sound passing through it. Sound passing through concrete is tested indirectly by testing the sound absorption in concrete and the sound reflection. Reflection can be tested easily with microphones and amplifiers.

For testing the sound absorption, there’s an instrument called Kundt tube. The collective system gives us the sound absorption coefficient from which we can calculate absorbed sound intensity.

Incident sound intensity – (reflected + absorbed) = sound passing through.