FEA of Biaxial and Triaxial Braided Composite for Effective Material Property Evaluation and Effect of Braiding Angle on the Dynamic Behavior

Braided composites are becoming popular especially for structural applications because of their natural tendency to conform to intricate shapes and more balanced properties than unidirectional laminates. In the present work three dimensional finite element analysis (FEA) of Biaxial and Triaxial braided composite have been performed by developing meso-scale model to evaluate the effective material properties of carbon/epoxy material system. A unit-cell based methodology has been adopted to account for the braiding style, matrix and the fiber-matrix interface. The simulations were performed using commercial FEA code ANSYS(R) and periodic boundary conditions (PBC) has been applied on the unit cells. By varying the braiding angle from 15 degrees to 75 degrees, the effective material properties were predicted and the variation of the engineering constants with the braiding angle was studied. The results obtained were in close agreement with the available experimental data. The technique of developing the meso-mechanical model for analyzing the mechanics of textile composite is very effective. It truly reflects the braided structure and corresponds with the actual pattern of the braided composites. In addition to that the dynamic response of the structure by changing braiding angle was investigated. The vibration analysis showed that the natural frequency of the structure is decreased by increasing the braiding angle.