Open hole compressive strength and damage mechanisms: maximum stress versus Hashin criteria

The open hole compressive strength and damage mechanisms of various T800/924C carbon fiber reinforced plastic laminates were estimated by a three-dimensional progressive damage model (PDM). The emphasis was put on the effect of Hashin and maximum stress criteria on the PDM estimations. The maximum stress criterion provided better overall correlation with the experimental data in terms of the matrix damage onset, ultimate strength and fibre damage pattern at the ultimate load. Despite both criteria being essentially the same for fibre compression, a scattered fibre damage pattern was predicted by Hashin criteria including fibre tensile damage as a result of the shear stress contribution. The matrix damage onset was significantly underestimated by Hashin criteria also due to the shear stress contribution. Nevertheless, neither Hashin nor maximum stress criteria could capture a satisfactory agreement with the experimental matrix damage pattern at the ultimate load.