live crack damage detection with local strain measurement on solid bodies subjected to hydrodynamic loading

Abstract The interaction of water free surface with solid bodies is object of interest in several mechanical, ocean, aerospace and civil engineering problems. The presence of impulsive loading and large local deformation leads to complex coupled dynamics. The possibility of live monitoring of these body could provide information about damage detection and fatigue life estimation. The definition of appropriate signal processing and modeling tools enabling the extraction of useful information from distributed sensing signals is a relevant scientific challenge. On the basis of previous works by some of the authors, this paper deals with the application of a method for real-time deformed shape reconstruction of solid bodies subjected to impulsive loadings using distributed numerically generated strain measurements signals, such as those produced by Fiber Bragg Grating (FBG) sensors. A numerical study is carried out considering a simplified model of the problem of hull structures subjected to hydrodynamic loading. The hull, analyzed in a simplified section, has been studied both in healthy condition and with the presence of crack damages. The potential for detecting, localizing and quantifying this damage using the reconstruction algorithm is investigated, by leveraging the proposed concept of control sensors, that are FBG sensors used for comparing reconstructed strains and/or displacements with measured quantities. The positioning and number of sensors and the effect of sensor layout on damage detection is investigated, with the aim of developing a real time damage detection methodology