Hierarchical uncertainty quantification of hybrid (riveted/bonded) single lap aluminum-CFRP joints with structural multiscale characteristic

Abstract

Due to multiple inevitable uncertainty sources from materials and geometry, the mechanical properties of the hybrid joints (HJs) are stochastic. This paper proposes an innovative method to predict the uncertainty of the mechanical properties of the HJs considering the structural multiscale characteristic. The proposed approach is based on multiscale numerical models ranging from the mesoscopic scale of the plain-woven CFRP to the macrostructure scale of the joint. In the mechanical performance simulation, multiple experimentally quantified uncertainty sources arising from different aspects (materials, geometry, and assembly) and different scales (mesoscopic, macroscopic) are introduced. The probabilistic uncertainty of high scale mechanical properties could be quantified scale by scale from low scale uncertainty variables with the adoption of the multiscale uncertainty propagation method. The quantitative results are in high agreement with the experiment, which proves the effectiveness of this method. Furthermore, the PCE-based uncertainty propagation framework makes it straightforward to implement the global sensitivity analysis of each variable, which helps identify crucial variables influencing the mechanical properties of the HJs. This work helps to deepen the understanding of the mechanism of fluctuations in the mechanical properties of the HJs.