In this paper, a new analytical model is developed to predict the strength oftwo-dimensional triaxial braided composite (2DTBC). According to the concept ofsubcell model, a representative unit cell of braided composite is divided into foursubcells, each of which is approximated as a stack of unidirectional composite plies. Inorder to investigate the interaction of braided angle and effective properties, it isassumed that the unit cell models of different braid angles have the same fiber volumefraction and the same thickness. Then, explicit equations can be obtained to describethe geometric parameters and to quantify the specific dimensions of subcellcomponents based on the manufacture provided properties and microscopic imageanalysis of realistic specimens. Micro-mechanical models are applied to estimate theelastic and strength properties of unidirectional plies. Classical Laminate theory andParallel and Series Bridge models are implemented to connect the strain and stressresponses of subcell components and effective responses of the unit cell. Hoffman andHashin failure criteria are used to examine the onset of failure for each subcellcomponent, which can then predict the progressive failure process and globalstress-strain response of the unit cell. The developed analytical model will then beutilized to predict the tensile strength (axial tension and transverse tension) of a+60°/0°/-60° 2DTBC and validated against experiments. Finally, the validated modelwill be used to study strength properties for 2DTBC of different braided angles. Theresults can provide insights for the design and optimization of composite structureswith similar braided architecture.
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