Hi,

I am currently simulating a bonded composite joint in Abaqus. The adhesive layer is very flexible and exhibits non‑linear plasticity. When I use the tensile test data of the adhesive in my material model, the simulation results do not match the experimental behaviour, likely because the adhesive responds quite differently in the actual joint configuration.

To improve the accuracy, I would like to use shear properties obtained directly from the joint tests. However, I cannot find an Abaqus material model that allows me to define the adhesive behaviour purely in terms of shear response. The material is nearly isotropic and performs much better in tension, so models like Drucker–Prager are not suitable. Using a von Mises formulation also does not capture the behaviour correctly.

Could anyone suggest an alternative approach for modelling a flexible, non‑linear adhesive without needing to write a UMAT?

Thank you.