Effects of structural parameters on the load distribution unevenness in CFRP hybrid bonded‐bolted joint

Abstract Carbon Fiber Reinforced Polymer (CFRP) Hybrid Bonded/Bolted (HBB) joint structures are distinguished for their superior jointing performance among current mechanical joint systems, making them a favored option for mechanical joints. These structures are characterized by many structural parameters, with the relationship between these parameters and jointing performance being notably complex. Additionally, the laminate's brittleness and the uneven distribution of bolt loads in multi‐bolt joint structures impair the overall jointing performance. To investigate the impact of structural parameters on the uneven load distribution within CFRP HBB joint structures and improve their jointing performance, a finite element analysis (FEA) model grounded in 3D Hashin failure criterion is developed. Validation of the model with experimental data confirmed the uneven load distribution among bolts in multi‐bolt joints. The study elucidated the influence of changes in structural parameters (overlap length, bolt‐hole spacing, and clearance fit) on the uneven load distribution and the connection strength of CFRP HBB joint structures. A negative correlation is found between the unevenness of load distribution and connection strength, offering insights for enhancing and researching connection strength in CFRP HBB joint structures. Highlights Developed a FEA model based on the 3D Hashin failure criterion for CFRP Bonded‐Bolted joints. Identified key factors affecting HBB joint load distribution and jointing performance. Evaluated the impact of overlap length, bolt‐hole spacing, and clearance fit on CFRP joints. Suggested design optimizations for enhancing the performance of HBB joints.