Combined loadings after medium velocity impact on large CFRP laminate plates: Tests and enhanced computation/testing dialogue

Abstract

The development and certification of aeronautical composite structures is still largely based on the pyramid of tests. This approach is extremely costly in terms of number of tests, especially at the level of coupons. Moreover, these tests are highly conservative, under uniaxial loading, and do not represent the actual behavior at structure scale. To overcome these drawbacks, a new methodology has been developed at the Institut Clément Ader, which uses a complex loading test rig for technological specimens. This research focuses on the combined loading after impact of CFRP plates and highlights a specific behavior quite different from the usual CAI (Compression After Impact) response at the scale of coupons. In particular, compression, shear and combined shear/compression loadings were applied to large Carbon Fiber Reinforced Plastics (CFRP) laminated plates and the interaction of the impact damage with the post-buckling behavior has been investigated.