Multiscale Modeling of Hole Damage Evolution During Dynamic Installation of Interference Bushings in CFRP

The dynamic installation of metal interference bushings has demonstrated significant potential for improving the mechanical performance of carbon fiber-reinforced polymer (CFRP) joints. However, the underlying mechanisms governing the remaining life enhancement remain insufficiently understood. This study employs a top-down multiscale modeling approach to elucidate this mechanism. A full-scale macroscopic model is coupled with a microscopic damage model to evaluate the influence of varying dynamic installation speeds on peri-hole damage. Macroscopically, a multirate dynamic installation model is developed to simulate progressive damage evolution and determine the overall material responses, used as input for microscopic modeling. Microscopically, a representative volume element (RVE) model is utilized, applying macroscopic strain fields as boundary to precisely capture localized damage mechanics, which can provide more detailed stress and damage distribution, especially near the hole. The proposed framework is experimentally validated using cross-sectional micrographs. The multiscale analysis reveals that higher installation velocities yield superior interference uniformity and a more balanced axial damage profile, fundamentally contributing to the enhanced fatigue performance of CFRP structures under cyclic loading.