Comparison the effect of pre-stress and curvature of composite laminate under impact loading

In this paper, the effect of preload on impact response of composite laminates is considered. To this aim, three specimens were manufactured and tested under 4 different impact conditions: 1- A curved laminate without preload. 2- A preloaded curved laminate, showing a lower radius of curvature due to the preload. 3- A curved laminate without preload but initial reduced curvature. The particular test conditions studied here allow estimating and discerning the effect of pre-stress and curvature on the impact response. Results show that the preload leads to an increased curvature, to which it follows that the maximum impact force and the damaged area increase significantly. The comparison of the impact response of the second and the third specimens show that, in the case of similar curvature, the preload leads to a lower damaged area. These results are particularly important for designing of curved composite components.