Structural response of composite sandwich panels impacted with and without compression loading

The results of an experimental study of the impact damage characteristics and residual strength of composite sandwich panels impacted with and without a compression lending are presented. Results of impact damage screening tests conducted to identify the impact-energy levels at which damage initiates and barely visible impact damage occurs in the impacted facesheet are discussed. Parametric effects studied in these tests include the impactor diameter and dropped-weight vs airgun-launched impactors. Residual strength results of panels tested in compression after impact are presented and compared with results of panels that are subjected to a compressive preload prior to being impacted.