Flexural behavior of single-lap joints of similar and dissimilar adherends

Abstract

During the past decades adhesively bonded joints have been intensively studied because of their extensive use from the simplest to the most complex constructions. The lap joint has become a standard test specimen with a view to assessing the strength and the properties of joints and for that reason numerous analytical relations have been proposed in order to predict the distribution of stresses within the joint as well as its strength. The present study concerns the experimental and analytical investigation of adhesively bonded single-lap joints between similar and dissimilar adherends in a three-point bending (3PB) arrangement. The experimental investigations include the effect of overlap length on the mechanical response and the strength of the joint. Single-lap joint coupons were manufactured from wood, Poly Vinyl Chloride (PVC) and titanium sheets and the corresponding joints were tested up to failure. The experimental results are grouped into two mains categories depending on the similarity of the adherends. The interfacial stress distribution within the adhesive, was computed using an appropriate analytical model and compared with Finite ElementAnalysis (FEA) results for the symmetric lap joints with very good correlation. The analytical model was used in order to assess the effect of different geometric and material parameters on joint stiffness and maximum normal and shear adhesive stresses at the ends of the overlap.