Experimental modal analysis of straight and curved slender beams by piezoelectric transducers

We present the use of piezoelectric disk buzzers, usual in stringed musical instruments to acquire sound as a voltage signal, for experimental modal analysis. These transducers helped in extracting natural frequencies and mode shapes of an aluminium beam and a steel arch in the laboratory. The results are compared with theoretical predictions and experimental values obtained by accelerometers and a laser displacement transducer. High accuracy, small dimensions, low weight, easy usage, and low cost, make piezoelectric pickups an attractive tool for the experimental modal analysis of engineering structures.