2025 ASEE Annual Conference & Exposition

The motivation of the work presented here is to provide students with tools to work with carbon fiber-epoxy structures, which are used in a large variety of industries and products. Related topics to carbon fiber-epoxy structures are covered around the middle of the semester in a “Design and Analysis” course which main topic is the Finite Element Method (FEM).
The lectures are presented in the following sequence:
1. Classification of composite materials including fiber and particle reinforced composites, and single and multilayer composites.
2. Mechanical properties - Review of stress-strain relationships of orthotropic lamina, elastic constants of an orthotropic material, stiffness and compliance matrices.
3. Finite element analyses of carbon fiber – epoxy structures including stresses, deflection, topology optimization, impact and natural frequencies and modes of vibration. Composite materials are modelled as a lamina or as a three-dimensional structure. “Lamina” models in the finite element method software Abaqus require six mechanical properties: two Young’s moduli (E1 and E2), a Poisson’s ratio (Nu12) and three Shear moduli (G12, G13 and G23), where 1, 2 and 3 define the orientation of the mechanical properties. Mechanical properties of three-dimensional models require nine “Engineering constants” three Young’s moduli (E1, E2, E3), three Poisson’s ratios (Nu12, Nu13 and Nu23), and three Shear moduli (G12, G13 and G23). These mechanical properties are determined using a) the rule of mixtures, or b) Chamis’ model. Improvements and optimizations of existing designs are included in the finite element labs, where students must solve design problems using optimization packages and/or choosing the number of layers and orientation of the fibers.
4. Manufacturing processes, including a hands-on session to prepare structures to later carry out experimental work.
5. Correlation of the finite element analyses mentioned above with experimental tests. In addition, damping properties are also determined.
All of the activities above are necessary to validate and verify new designs in the industry. Furthermore, these types of hands-on laboratories including finite element analyses and experimental tests are highly encouraged by ABET, as it has been documented that these types of activities help keeping students engage in courses.
Results show that students enjoy working with hands-on activities such as labs using a commercial finite element method code and taking part in experimental work. Average grades in this part of the course are typically 90%, while the average grades of the exams may be around 70%.