A three-dimensional numerical analysis of the effect of embedding cylindrical microwire sensors on the compressive strength of carbon-fiber reinforced composite laminates
The objective of this 3D finite element analysis study is to evaluate the effect on compressive strength of a laminated composite specimen, when cylindrical microwire tubes are embedded inside the structure. These microwire tubes cause geometric disturbances in the fiber architecture of laminated composite specimens and act as defects, resulting in the potential weakening of the structure. Hexahedral finite elements are used to study the three-dimensional state of stress in the vicinity of the free-edge and the interface of the embedded sensor and neighboring plies. Finite element models of two laminated composite stacking sequences, 22 and [(90/0/90)3 /90/0]s with octant symmetry are developed. Induced thermal stresses in composite specimens post-curing are also included in the finite element model. The impact of out-of-plane, interlaminar stresses is studied on the onset of failure in compression. Stress concentrations developed due to the presence of the sensor and resin pocket at different locations are recorded to compare their respective criticality. Lastly, numerical progressive failure analysis is performed using different failure criteria to compare the computational results to historically available experimental data.
Thesis (M.S.)--Wichita State University, College of Engineering, Dept. of Aerospace Engineering