Notched compression strength of 18-ply laminates with various percentages of 0° plies

Abstract

The use of knockdown factors (percent reduction of undamaged compression strength) to account for flaws such as impact damage or holes have been used to infer the notched strength of laminates. It has been observed that this criterion tends to over-predict the strength of laminates with a high percentage of 0° plies. This paper examines some limited data from the literature and presents new data that compares knockdown calculated notched compression strength values with those measured experimentally for laminates with various percentages of 0° plies. Results show that the trend of over-predicting the notched compression strength of laminates as the percentage of 0°plies increases, based on a knockdown factor, is observed, but the difference can be within scatter except at very high percentages of 0° plies.

Keywords

Compression-After-Impact open-hole compression percent 0° plies knock-down factors

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