A study on the robustness of two stiffened composite fuselage panels

The European Commission project COCOMAT aimed at exploiting the large reserve of strength in composite structures through more accurate prediction of collapse. As part of the research program, curved stiffened composite panels of various designs have been manufactured and tested in compression. In the current pool of experiments it is possible to observe the scatter in results caused by manufacturing defects and material variations. In a bid to account for the scatter in design, two qualitative measures of robustness, called Robust Indices, have been derived so that effective comparisons can be made. The first measure quantifies robustness of structures with respect to their input variables while the second measure quantifies the overall robustness of a structure.