PSI - Issue 64

1856 Tommaso Papa et al. / Procedia Structural Integrity 64 (2024) 1849–1856 8 Tommaso Papa, Massimiliano Bocciarelli, Pierluigi Colombi, Angelo Savio Calabrese / Structural Integrity Procedia 00 (2019) 000 – 000 5. Conclusions A cyclic cohesive zone model for the description of the interfacial bond behavior has been adopted. In particular, the identifiability of the fatigue model parameters was investigated. The procedure is based on the use of virtual data, i.e., data generated numerically by simulation, and which are then provided in input to the inverse analysis algorithm. Different analyses have been performed by varying the number and the value of the sought parameters and the type and amount of experimental information adopted. These input data have been perturbed by a noise level before being fed into the optimization algorithm to investigate the robustness of the inverse problem solution. Several noise extractions, sufficient to guarantee converge of the algorithm, have been adopted to provide a statistical characterization of the results through a Monte Carlo analysis. Based on the first obtained results, some concluding remarks can be drawn. The proposed stochastic inverse analysis procedure resulted to be accurate in investigating the identifiability of the sought model parameters by using measurements that can be generally taken in DS test configuration. In both scenarios, the information provided by displacements measurements resulted to be sufficient for the parameters identification. However, additional strain measurements resulted in the reduction of both the identification error and the associated standard deviation. Finally, the adoption of a meta-model reduction technique based on a polynomial interpolation scheme resulted to be effective in reducing the computational effort of the finite element operator. 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