Determination of critical delamination diameter of laminated composite plates under buckling loads

The effect of a single circular delamination around the circular hole on the critical buckling load of woven fabric laminated composite plates has been investigated experimentally and numerically. The determination of the critical delamination diameter for laminated composite plates has been intended by using three dimensional buckling analysis. For the experiments, cross-ply laminated composite plates with delamination and without delamination have been produced. The experimental critical buckling loads of plates have been found by clamping from the two edges and then these results have been compared with the results obtained from the numerical analyses. For the numerical analyses, ANSYS 6.1 FEA program has been used. It has been seen that the results obtained the numerical buckling analyses are very close to the experimental results. In the light of this harmony, the numerical analyses for different delamination diameters and fiber orientations have been done and from these analyses, it has been seen that the important decreases occur in the critical buckling loads after a certain value of the delamination diameter and the different fiber orientations also affect to these loads.