Influence of diameter and boundary conditions on low velocity impact response of CFRP circular laminated plates

Low velocity and low energy impact tests were carried out on CFRP circular laminated plates, in order to investigate the effect of specimen dimensions and boundary conditions on dynamic behaviour and material damage. Two different diameters and constraints were tested. Numerical simulations of specimen impact response were performed by a finite element program and compared to experimental results. Tests indicated that both dimensions and boundary conditions affect response and damage, higher target stiffness resulting in greater energy absorption and more extended delamination. An empirical relationship with absorbed energy and with maximum contact force, independent of the test configuration, was found for the delamination area. The main features of contact force history were correctly predicted by numerical analysis, although disagreement was observed between numerical and experimental results due to damage.