Experiments on shear performance of integrated 3D composite sandwich structures

A new type of 3D composite sandwich structure with foam core reinforced by composite columns, which can be called integrated 3D composite sandwich structure, was designed, fabricated and studied. The integrated 3D composite sandwich structure inherited the advantages and improved the shortcomings of the traditional foam core composite sandwich structures. All types of the samples with different consisting materials and structural parameters were tested and analyzed under tension shear load. The results show that the shear properties of the integrated 3D composite sandwich structures are obviously better than those of the traditional foam core composite sandwich structures and due to the fact that the composite columns bond the two face sheets and the core together. Moreover, the stitch-bonding effect is more obvious for the better shear properties foam. The structural parameters have significant influence on the shear properties, especially the diameter of composite columns and the distance between composite columns. However, the variety of these parameters result in a corresponding change of the mass and then effect the specific shear properties. Consequently, it is necessary to find a balance among these parameters in order to get the optimal properties.