Efficient Post-elastic Analysis of Bonded Joints by Standard Finite Element Techniques

摘要

A simplified finite element approach based on reduced models with minimum degrees of freedom was applied to the post-elastic analysis of bonded joints. The reduced model describes the adherends by means of structural elements (beams or shells) and the adhesive by a single strip of solid elements (plane-stress or brick). Internal kinematic constraints were applied to link the adherends and adhesive meshes. The accuracy and the efficiency of the reduced models in providing the force-displacement curve of T-peel joints were evaluated through a numerical test campaign by comparison with full finite element analyses. The test campaign was designed as a 2-level factorial experiment involving four variables: the skew angle of the T-peel (45 and 90°), the thickness of the adherends (2 and 3 mm), the material of the adherends (aluminium and steel) and the stress-strain behaviour of the adhesive (brittle and perfectly plastic). The results show that the reduced model reproduces with fair accuracy the load-displacement curves of the joints at a fraction of the computational cost of the full model. The elastic stiffness, the yield load and the deformation energy were predicted within an error of 7%, 15% and 36%, respectively, with processing times that were typically 50 times shorter than the full model.