Nonlinear finite element analysis of stress and strain distributions across the adhesive thickness in composite single-lap joints

• Published in: Composite structures Vol. 46; no. 4; pp. 395 - 403
• Main Authors: Li, Gang, Lee-Sullivan, Pearl, Thring, Ronald W
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.12.1999; Elsevier Science
• Subjects: Applied sciences; Computational techniques; Exact sciences and technology; Finite-element and galerkin methods; Machine components; Mathematical methods in physics; Mechanical engineering. Machine design; Nonlinear finite element analysis; Physics; Seals and gaskets; Single-lap joints; Stress and strain distributions; Single-lap joints; Stress and strain distributions; Nonlinear finite element analysis; Elastic modulus; Stress analysis; Free boundary; Crack formation; Lap joint; Cohesive end; Numerical method; Wedge; Edge crack; Finite element method; Crack bridging; Experimental result; Adhesives; Composite materials; Stress distribution; Adhesive joint; Shear stress; Strain distribution; Corner joint; Two dimensional analysis
• ISSN: 0263-8223; 1879-1085
• DOI: 10.1016/S0263-8223(99)00106-3

A geometrically nonlinear, two-dimensional (2D) finite element analysis has been performed to determine the stress and strain distributions across the adhesive bond thickness of composite single-lap joints. The results of simulations for 0.13 and 0.26 mm bond thickness are presented. Using 2-element and 6-element mesh schemes to analyze the thinner bond layer, good agreement is found with the experimental results of Tsai and Morton. Further mesh refinement using a 10-element analysis for the thicker bond has shown that both the tensile peel and shear stresses at the bond free edges change significantly across the adhesive thickness. Both stresses became increasingly higher with distance from the centerline and peak near but not along the adherend–adhesive interface. Moreover, the maximum shear and peel stresses occur near the overlap joint corner ends, suggesting that cohesive crack initiation is most likely to occur at the corners. The dependence of stress and corresponding strain distributions on bond thickness and adhesive elastic modulus are also presented. It is observed that the peak shear and peel stresses increase with the bond thickness and elastic modulus.