Numerical Analysis of Zero Strain Point Behavior in Adhesively Bonded Joints Using Surface-Based and Element-Based Cohesive Zone Models

Adhesively bonded joints, especially single-lap joints (SLJs), have gained many applications in the aerospace and automotive industries due to their lightweight and efficient structures. The present study is an attempt to highlight the proper detection of the Zero Strain Point (ZSP) through numerical modeling. Various models were developed and analyzed in 2D and 3D FEM with cohesive elements and surface-based cohesive interactions. The epoxy adhesive proved better strain distribution in locating ZSP and replicating force-displacement behaviour; polyurethane was less versatile in some geometries. This paper points out ZSP prediction in FEM simulations through material property tuning and refinement of the mesh.