Quantitative Damage Diagnosis Method under Vibration Conditions Based on Two-Dimensional Gaussian Model with Phase Synchronization Damage Index

In civil, mechanical, and aerospace engineering, structures are subjected to complex high-frequency vibrational loads during operation. Diagnosing structural damage under these conditions is essential for ensuring safe operation. This paper tackles the challenges in monitoring the structural health of guided wave structures during operation and proposes a damage diagnosis method based on two-dimensional Gaussian model. First, this paper examines the impact of various vibration conditions on guided wave signals and introduces a new damage index-the phase synchronization damage index. This index, together with the spatial phase damage index, constitutes a two-dimensional feature sample set. Using this feature sample set, the optimal number of samples is determined, and both a baseline Gaussian model and a dynamic monitoring Gaussian model are established. The weighted sum of multi-path distance metrics is then employed as a quantitative damage index for diagnosis. Experiments were conducted on aluminum alloy plate structures with varying degrees of crack damage under different vibration conditions. The results demonstrate that the proposed method can quantitatively monitor damage under different vibration conditions, achieving high accuracy in estimating the degree of damage.