Date of Award
Master of Science in Aeronautics and Astronautics
Aeronautics and Astronautics
Committee Member 1
Committee Member 2
Interlaminar damage (delamination) is one of the predominant forms of failure in laminated composites, which is broadly used in aerospace, astronautical and automobile industry and many other fields. Engineering problems about damage tolerance and structure durability requires the ability to simulate mixed mode delamination in laminated composites. The objective of the research is to develop an implicit scheme for a recently developed damage-type cohesive zone model (CZM) with an associated systematic calibration method. The CZM is formulated based on thermodynamics, and the damage evolution is derived with the principle of maximum dissipation. A stable implicit scheme using the Newton–Raphson method is developed to solve the model iteratively. A finite element framework consisting of double-cantilever beam (DCB) , end-notched flexure (ENF) and mixed-mode beam (MMB) models and properly chosen mesh density is built to incorporate the present CZM. A systematic calibration method is then established to calibrate the damage parameters from experimental results of interfacial parameters and flexural tests. The present model is found to yield consistent and accurate results in finite element simulations. Specifically, it’s shown to be able to reproduce the critical energy release rates and maximum loads that the structure can endure. The maximum loads are found to be also affected by the interfacial strenghth. Conclusively, the present model could be used in engineering practice because of its superior accuracy and stability.
Du, Haodong, "Simulating composite delamination with a damage-type cohesive zone model" (2018). Open Access Theses. 1378.