Elasto-plastic adhesive joint design approach by a radial point interpolation meshless method

For efficient use of adhesive joints, reliable prediction techniques should be made available to the designer. Simulation of these joints' behaviour is usually performed using the Finite Element Method (FEM). However, it is known that, in adhesive joints, the adhesive thickness (t(A)) is much smaller than the adherend thickness (t(P)), thus requiring a highly refined mesh to produce good results. Linked to this, the adhesive has to withstand high strains, causing mesh distortion and hindering the resolution. In these cases, meshless methods can be a good alternative. This work aims to implement the von Mises (vM) and Exponent Drucker-Prager (EDP) criteria combined with a meshless formulation based on the Radial Point Interpolation Method (RPIM), for the strength prediction of adhesively-bonded single-lap joints (SLJ). Validation with experiments is undertaken for joints with brittle to ductile adhesives, with varying overlap lengths (L-O). Stress and strain distributions were plotted in the adhesive layer, and the failure load (P-m) was assessed by strength of materials failure criteria. Significant adhesive and L-O effects were found on P-m. The RPIM proved to be a promising tool to predict the behaviour of bonded joints, although some limitations were found by using strength of materials criteria.