Strength Analysis And Test Of Bicycle Frame In3-d Tubular Woven Carbon Fiber Composite

Tube is the basic component which is widely used in mechanical structure. The tube which are composed of resin and carbon fiber has light weight, high strength ratio and modules ratio, excellent fatigue resistance, good corrosion resistance, etc.3-D tubular woven carbon fiber composite is developed with the3-D circular weaving method. Where the warp yarns are arranged in the circumferential direction and driven by the vertically moved heddles to form a plurality of fells, each fell correspond to a layer of fabric. After the weft yarns are insert into fells by the shuttles, the warp yarns switch their positions to fix them in the fabric. Binder yarns interweave in the thickness direction to enhance the mechanical properties of the interlayer structure. Study for microstructure and elastic properties of the composite is necessary.In this paper, based on the true structure of the3-D tubular carbon fiber composite, we established the meso-geometric model and finite element model to predict the mechanical properties of the composite with the stiffness averaging method and finite element method, then study its application on the bicycle frame. The chief content can be fallen into three parts as below:In the first part, a new mechanical model was put forward to predict the mechanical properties. The model adopted raceway shape as the cross-section of yarn, and prediction methods of volume fractions was established based on the micro structure and geometric parameters of it. And use the volume averaging method to predict the elastic properties of the composite.In the second part, using CAD software to establish the geometry model of unit cell, and transformed it into FEA software to evaluate their elastic properties. The equivalent elastic parameters and the stress distribution were obtained. The results shows that the predicted values using finite element method agree well with the theoretical calculation values, which means the FEA method is available and the unit cell structure is correct. And continue to analyze the impact of layers of a single cell on the elastic properties.In the third part, in order to facilitate the connection between carbon fiber composite tube and connectors on the bicycle frames without affecting its mechanical properties, the optimal type of connection was picked out among three different binding modes by using Virtual prototype technology and finite element technology. The analysis results of this paper should be helpful for designing bicycle made of carbon fiber composite.