A general method for numerical identifiability and sensitivity analysis of failure criteria for continuous fibre-reinforced plastics

Abstract

Modelling the static failure of fibre-reinforced composite laminates is a challenging problem, as the parameters of the relevant mechanical models might not have a physical interpretation. Failure parameters are usually determined experimentally, where the parameter fitting and experimental design can be non-standard and intricate. In order to improve efficiency in designing mechanical experiments for the fitting of composite failure model parameters, a general method for quantifying the sensitivity of failure criteria parameters to failure stress states has been developed. This method helps selecting the failure stress states with regards to a failure model that result in the most robust fit of the model parameters. The method is demonstrated on the commonly used Tsai–Wu and Puck failure models, but is valid for a wide range of other models as well. The practical application of this method is also demonstrated by evaluating an experimental data set.