STRUCTURAL MODAL MODIFICATION OF NON-PROPORTIONALLY DAMPED SYSTEM

: Undesirable levels of vibration are an especially common occurrence in modern engineering. Being able to effectively isolate and solve the problem areas of a structure would prove to be a valuable tool in correcting these levels of vibration. This work presents a method for modal synthesis that enables the structural properties to be purposefully changed and that can be applied to systems with non-proportional damping. In order to present the methodology in detail, the case where additional elements are made of aluminium foam are presented. These have very unique properties and broad applications. This methodology is demonstrated, for better understanding, on an example of a beam with added aluminium foam elements. A beam with aluminium foam was chosen since its connection with the base beam changes the inertial as well as stiffness and damping properties of the resulting system.