Effect of the grid shape of the composite plate structures on the buckling load

Effect of the grid shape of the composite plate structures on the buckling load

Buckling of the composite plates is an important branch of the research in the field of composite structures stability. Buckling load of the cells in the tiangular and rhombic shapes is investigated experimentally and numerically in this study. All samples were composites made of glass - epoxy cured at room temperature. Composite plates were made out of glass fabrics. Ribs were made of glass fibers with the density of 2500 kg/m3 the resin with the density of 1200kg/m3. Three experimental sample for each type of shape were cured and the results were compared with reference samples. These samples were cured using the manual method. All the specimens were subjected to pure axial loading for the buckling experiment and the different forms of buckling were examined. Results showed that the overall buckling load increased by 27 to 44 percent and the buckling load to weight ratio (specific load) increased by 2.5 to 9 percent, relative to the reference case. Clearly, it was observed that the addition of the ribs to the reference case increases the buckling load of the samples in equally weight samples. Finally, the finite element model for the buckling behavior of the reference and grid plates were drived and relatively good agreement was obsereved between numerical and experimental results of the under buckling structures.