The Influence of the Weight Loss upon Natural Frequency Changes in Case of Severe Defects

The paper presents a research regarding the use of a "virtual" material in order to compensate the loss of mass in the case of the damaged beam. Because of the loss of mass, the frequency of the beam suffer an increase over the natural frequency of the undamaged beam and so we have proposed the use of this material, having the same density with the density of the beam, in the gap left by damage.