OFFSET AND SUB-HARMONIC FREQUENCY COMPONENTS IN THE HIGHLY NONLINEAR DYNAMIC RESPONSE OF DAMAGED STRUCTURES

摘要

An extensive parametrical investigation, based on a theoretical approach, evaluates the complex oscillatory behaviour in multi-cracked highly nonlinear structures under excitation. In particular, we have focused our attention on a cantilever beam with several breathing transverse cracks and subjected to harmonic excitation perpendicularly to its axis. The numerical simulations have been performed by varying the main parameters influencing the dynamic behaviour of the structure, i.e. the crack number, depth and position, as well as the force amplitude, frequency and position.