Analytical Stress Analysis in Single-lap Adhesive Joints under Buckling

Adhesive joints find numerous applications in various industrial fields. They represent a valid alternative to traditional joining methods. Much of the available scientific literature has focused on the study of adhesive joints subjected to tensile loads. There have also been numerous studies concerning the stresses distributions in the adhesive layer. However, in real case applications, adhesive joints could also be subject to cyclic tensile-compression loads and therefore could be subject to buckling phenomena. The objective  of  the  present  paper  is  to  investigate  the  numerical  study  of  the  stress  distribution  in  the adhesive layer under buckling condition. The study presented develops with the analysis of a single-lap joint  with  a  combination  of  steel  adherends  and  three  different  structural  adhesives  with  different thickness  and  Young’s  modulus.  The  joints  are  modeled  using  FE  ANSYS©19  software.  Through numerical  analyzes,  it  is  possible  to  predict  the  value  of  the  critical  load  for  each  single  analyzed combination. Once the critical load is determined, the stresses in the middle plane of the adhesive layer are determined. The results obtained show that for small adhesive thicknesses (i.e. 0.30 mm) it is possible to reduce the stress peaks - with the same critical load value - by using structural adhesives with low elastic modulus (e.g. silicones).