Narrow-band diffuse ultrasonic wavefield measurements in a network of reciprocal transducers for monitoring of a large concrete floor slab
Piezoelectric transducers were attached in a grid on the surface of an 8 x 2 x 0.08 m concrete floor slab. Through an automated, iterative scheme these were used to transmit and receive 50 kHz, continuous, sinusoidal signals, which were sampled by a multi-channel lock-in amplifier. The measured amplitude and phase were used to locate inflicted damage by detecting deviations from baseline measureme
