ON A GENERAL MODEL FOR DAMPING

Abstract

When a structure exhibits a damped dynamic behavior that does not conform to the classical and well-known viscous or hysteretic models, a more general approach must be sought. Several questions may then be raised, like (i) in which theoretical background should one base the investigation?, or (ii) can one apply common modal analysis tools to solve the problem? Recent works have shown that some types of materials and therefore structures demand a more rigorous behavior description and that it seems possible to address the problem by means of the theory of fractional derivatives, leading to a model in terms of general damping parameters. Such an approach reveals itself somewhat complicated to implement in practice and some simplifications are necessary. The authors discuss the use of a generalized damping concept for modeling the dynamic behavior of linear systems and show how this concept allows for a clearer interpretation and explanation of the behavior displayed by the common viscous and hysteretic models.