The majority of current Adaptive Optics (AO) systems do not compensate properly for vibrations within the optical path. For this reason the mitigation of vibration effects in astronomical AO systems is extremely important. The mechanical vibration effects, acting in the science light propagation path, strongly affect the performance of the LBTO/AO system. A frequency-based analysis of the pyramidal wavefront sensor data (PWFS) and the accelerometers network data (OVMS+) on the telescope structure was done in order to identify the principal mechanical vibration frequencies.