On the computation of interface stresses by finite elements for sandwich materials

In this article, we recall the methods generally followed to compute stresses, and then develop a simple alternative. In order to improve the accuracy and stability with very few elements, we improve the proposed method to a second one. The latter method is then assessed on two examples to compute interface stresses of a sandwich structure. The robustness of the method in terms of convergence speed, accuracy and stability is demonstrated. The simplicity of formulation and implementation is also emphasized.