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The objective of this work is to develop a methodology to predict matrix damage initiation and evolution in laminated composites subjected to monotonic cooling using discrete damage mechanics and a careful characterization of the required temperature-dependent material properties. Since prediction of thermo-mechanical damage requires precise knowledge of the temperature-dependent properties of the material, back-calculation of fiber and matrix properties from different sources is included. The proposed methodology is flexible, in that it can be adapted to the availability of experimental data. A compilation of literature data is developed to estimate the properties of several fiber and matrix systems. Prediction of lamina and laminate temperature-dependent properties are compared with available data. Furthermore, temperature-dependent fracture toughness of four material systems are estimated from available crack density data. For the material systems studied, it is found that temperature-independent fracture toughness is satisfactory for prediction of damage initiation, evolution, and saturation.

Well-designed laminated composites do not fail suddenly but rather develop microscopic progressive damage that leads to changes in macroscopic material response, such as matrix cracks, stiness reduction, and failure. Simulation techniques are able to predict damage initiation and evolution as a function of service conditions. A method for obtaining material properties for damage analysis of Glass and Carbon ber composites is proposed a using progressive damage analysis (PDA) model implemented in Abaqus. The predictive capability of Progressive Damage Analysis (PDA) methods relies on material properties that characterize the ability of the composite to resist damage initiation and to delay damage progression. Although elastic moduli data and standard experimental methods exist, data and methods do not exist for damage-related properties. However, experimental data displaying macroscopic eects of damage (e.g., crack density and stiness reduction) exists for a number of material systems. These experimental methods are suciently standardized to be used for other material systems. The purpose of this study is to develop a method to obtain the missing material properties by adjusting their values so that the predicted material response matches experimental data. This methodology is based on minimizing the error between simulation predictions and available experimental data. Once the material properties are obtained, the simulation predictions are compared to a broad set of experimental data. Finally, sensitivity and convergence of Abaqus PDA is also studied.