OS1327-375 一方向CFRP積層板の縦方向切欠きスプリッティング強度とその寸法依存性

Abstract

The effects of specimen size as well as notch size on the onset of longitudinal splitting in a unidirectional carbon/epoxy laminate have systematically been examined. For this purpose, static tension tests were performed on one-, two- and three-dimensional geometrically similar specimens containing a central circular hole of different diameters, respectively, at a constant nominal strain rate. The experimental results showed that no significant effect of 1D scaling on splitting strength was observed, regardless of the notch size. A tendency for splitting strength to slightly increase by about 5% with 1D scaling up in the thickness dimension was observed, while it was not appreciable overall. On the other hand, the splitting strength had a tendency to decrease by about 20% with increasing in-plane dimensions as well as in all the dimensions, regardless of the notch size. The 3D scaling effect in the splitting strength was governed more by the 2D scaling effect involved since the 1D scaling effect was much smaller, and accordingly the 3D scaling effect exhibited a tendency to decrease in the splitting strength as in the 2D scaling effect. Development of a phenomenological model that can describe the multi-dimensional scaling effects is also attempted.