Lang, Daniel, authorRadford, Donald, advisorHerber, Daniel, committee memberChong, Edwin, committee memberHeyliger, Paul, committee member2022-05-302022-05-302022https://hdl.handle.net/10217/235295Many industries are exploring the application of composite materials to structural designs to reduce weight. A common issue that is encountered by these industries, however, is difficulty in developing structural geometries best suited for the materials. Research efforts have begun to develop optimization methodology to help develop structural shapes but have thus far only partially addressed optimization of the geometry. This dissertation provides a literature review of past efforts to develop optimization methodologies. Through that review it is identified that the subprocesses required to fully optimize a composite structure are mold shape optimization, ply draping analysis, kinematic partitioning, connection and joint definition, ply topology optimization and manufacturing simulations. To date, however, these subprocesses have primarily been applied individually and have not been integrated to develop fully optimized designs. In this research, a methodology is proposed to integrate established composite design and subprocesses to develop optimized composite structures. The proposed methodology sequentially and iteratively improves the design through mold shape optimization, ply draping analysis, kinematic partitioning, connection and joint definition, ply topology optimization and manufacturing simulations. Throughout the proposed methodology, checks are also integrated to ensure that the developed design meets design objectives and constraints. To test the methodology a case study is conducted to develop composite rail vehicle structures. As part of this case study, it is hypothesized that a composite structure designed through a fully integrated methodology will demonstrate reduced costs, mass and improved manufacturability compared to a structure where functions have only been partially integrated. When the proposed fully integrated methodology is applied to create a case study design, the hypothesis is validated. The design generated by the fully integrated optimization methodology has a 37% lower mass and a 56% lower cost to manufacture than a design that is developed through a partially integrated methodology. The case study also demonstrates that structures developed through the proposed methodology have improved manufacturability.born digitaldoctoral dissertationsengCopyright and other restrictions may apply. User is responsible for compliance with all applicable laws. For information about copyright law, please see https://libguides.colostate.edu/copyright.integrationcompositesText