About the excitation dependency of risk tolerance mapping in dynamically loaded structures

To demonstrate the viability of this risk tolerance concept, accurate ESPI-based receptance maps’ estimations of the experimental structural dynamics of a lightweight rectangular plate were here used, with two distinct excitation sources. ESPI technology actually permits a precise estimation of superficial strain FRF maps, which, with the aid of a constitutive model of the material and of a fatigue method for duration prediction, can lead to frequency-to-failure maps, as function of the specific excitation location and signature. Once a proper risk index and its acceptance threshold are formulated, the risk index maps can grade the failure risk as function of the real structural dynamics and boundary conditions of the real component, of the excitation location and of its dynamic signature. Examples and details are given specifically as the excitation changes location, in order to show how the most advanced experiment-based knowledge available can augment the fidelity of the proposed risk tolerance and defect acceptance mapping.