Assessment of Residual Elastic Properties in Damaged Composite Materials

Structural composite materials applications are increasing due to their optimal mechanical properties. However, from factors that limit their widespread applications, especially for applications involving structural components, the complexity of damage evolution significantly restricts its applicability. This paper aims to use finite element method (FEM) modeling using ABAQUS for different impact loading conditions to develop a stepwise damage model of laminated structures by considering the elastic properties of damaged composites. Therefore, in order to predict the kind and extent of damage based on the laminate thickness, a 3D damage model with solid elements was developed and integrated into the Abaqus/Explicit finite element code. The results showed that the elastic properties of damaged composites basically depend on different damage parameters such as fiber compression (FC), fiber tension (FT), matrix compression (MC), matrix tension (MT), and shear (SHR). The applied impact loads give different force-displacement relations leading to other damage parameters and elastic modulus. However, the MT and SHR damage parameters affect the elastic properties of the damaged composites independent of load and displacement values. A continuous force-displacement curve was assumed to account for the variation of the elastic modulus in the finite element model.