Numerical Modeling of Adhesively Bonded Single-Side Strap Joints: Steel-to-Hybrid Sisal-Glass Reinforced HDPE Composite Debonding Under Fatigue Loading

Abstract This study presents a numerical modeling approach for analyzing the debonding behavior of adhesively bonded single-side strap joints made of steel-to-hybrid sisal-glass reinforced HDPE composite under fatigue loading. The objective of the study is to investigate the fatigue-induced debonding behavior of adhesively bonded joint. Methods employed in this study are a cohesive zone model based finite element method employed to simulate the progressive damage and failure mechanisms at the adhesive interface. The study investigates the effects of key parameters, including adhesive thickness, cohesive fracture toughness, fiber-to-matrix weight ratio, temperature, and moisture exposure on fatigue life and damage progression. The numerical results are validated against experimental data and analytical solutions, demonstrating the model's accuracy in predicting fatigue-induced debonding. Sensitivity analyses are performed to assess the influence of varying material and geometric parameters on joint durability. The findings provide insight into optimizing adhesive joint design for automotive applications, particularly for lightweight composite structures. It is recommended that future research incorporate detailed experimental testing under fatigue loading to confirm the predictive accuracy of the FEM simulations and CZM approach.