Simplified Analytical Procedure for Prediction of Fracture Damage in Composite Structures

"It is proposed to develop simplified composite analytical procedure (SAP) for naval joint design that will perform: 1) material constituent analysis (MCA), 2) material uncertainty analysis (MUA), and fracture damage, and the percentage contribution of eachmaterial constituent to failure mechanisms. The SAP will then be utilized by an integrated computational design tool, that automatically iterates all analytical procedures such as: 1) MCA, 2) MUA, 3) progressive failure analysis (PFA), and 4) probabilisticfailure analysis under hygral conditions. SAP will be used to predict, under all operational conditions (temperature/thermal gradient, humidity, oxidative/corrosive agents): 1) constituent/ply mechanical properties, 2) property degradation by implementingthe multifactor interaction model, and 3) effects of bond line strength/thickness/voids on failure. PFA can automatically integrate SAP to predict the durability/reliability of a typical marine composite joint/structure, including determination of thefailure mechanisms contribution to the critical damage events (crack initiation/propagation), residual strength, sensitivity of joint design parameters (e.g. configuration, bond-thickness, ply-schedule) to the probability of failure. As a synergisticdemonstration SAP and PFA will perform an integrated joint design analysis to identify: 1) failure mechanisms (e.g. delamination or disbond), 2) strain energy release rate, 3) durability