Effect of single-bolt repair on compression capability of carbon/epoxy composite laminates containing impact damage

The efficiency of single-bolt repairing on the compression capacity of carbon/epoxy composite laminates containing impact damages was experimentally reported. The compression bearing capacity and failure modes of carbon/epoxy composite laminates with impact damage under three different level energies were studied. Simultaneously the efficiency of single bolt repairing on the compression capacity of the above-mentioned impacted carbon/epoxy composite laminates was investigated together with failure behavior based on digital image correlation (DIC) technology. The results show that the compressive load capacity of the laminated plate decreases with the increase of the impact energy, and the impact damage destroys the stiffness symmetry of the carbon/epoxy composite laminates, resulting in asymmetric local buckling deformation from the initial stage of loading. Bolt repairing can restore the overall symmetry of the carbon/epoxy composite laminates, inhibit the local buckling of the delaminated area to a certain extent, and improve considerable repair efficiency. This work is helpful for the decision of fasten repairing strategy and the definition of repair damage tolerance for composites structure.