Numerical estimation of in-service damages’ effect on the load-bearing capacity of composite aircraft structures elements

Abstract

AnnotationOne of the main problem on the way to the effective integration of polymer composite materials in aircrafts’ primary structures is the high sensitivity to various defects and damages. The main task in design is to create a composite aircraft structure such that any possible damage (defect) does not lead to a decrease in its load-bearing capacity below the limited load level. As a rule, in practice, this problem is solved by performing a large number of tests. The introduction of a “Building Block” approach based on modern numerical methods will reduce the required number of tests. In this paper, we consider the nonlinear numerical analysis to estimate the residual load-bearing capacity of a composite structure. It allows taking into account different progressive failure processes and their interaction within a single model. On an example of the composite panel with a “cut” it is shown that this method results in a sufficiently accurate residual strength prediction. However, due to its complexity, it is unsuitable at the early stages of design development. For this task, we developed a simplified numerical analysis method. The obtained results validated by comparison with the available test data and with more detailed nonlinear analysis.