ABSTRACT
There are two groups of methods used to examine the characteristics of energy dissipation in the materials under cyclic loading. The methods of the first group are the direct methods, based on the direct measurements of dissipated energy values. The methods of the second group are indirect methods, where the amount of dissipated energy is determined from changes in the other parameters (such as amplitudes, frequencies, lags, etc.). Energy and thermal methods, as well as the method of the hysteresis loop, fall into the group of direct methods. The method of free damped vibrations, the method of the resonance curve, and the phase method fall in the group of indirect methods.
