Multi-scale modelling of 3D multi-layered braided composite tubes

The mechanical behavior of 3D multi-layered braided composite tubes was analyzed using a multi-scale modelling approach. Considering the braiding parameters and the fiber volume fraction of the composite tubes, firstly a unit-cell of the composites was determined based on the motion of yarn carriers and modeled using TEXGEN software. The unit-cell was imported into finite element software to calculate its meso-scale material properties. In this calculation the yarns in the unit-cell were assumed to be solid constituents without considering each filament in them, i.e., a meso-scale approach was adopted for the yarn modelling. Then, the calculated material properties were used to analyze macroscopic deformation behavior of the composite tubes using finite element analysis. The validity of the current mesoand macro-scale analysis will be discussed for designing composite tubes such as mountain bike (MTB) frames, e.g., in finding optimums of the fiber volume fraction, the braiding angle, and the number of layers.