Using Transmissibility to Detect and Quantify Structural Damage

Structural health monitoring is often based on local and off-line non-destructive evaluations. Amongst the techniques under development one can outline those using mechanical vibrations. The fundamental principle of the mechanical vibration based methods relies on the fact that damage alters the dynamic properties of a structure. Defining proper indicators that take into due account those modifications allow us to have a measure of damage. It is very important to develop methods that are able to simultaneously detect the existence of damage and to quantify its extent in mechanical systems and structures. In this paper the authors propose an improved indicator to detect and quantify structural damage, using vibration response data directly measured along a structure. This data is processed to generate transmissibility functions that are subsequently used for damage identification in a numerical simulated case study