부산대학교 도서관

In this work, the bending modal properties of three-dimensional (3D) braided composites were investigated withthe experimental and numerical methods. Three braided angles were selected to study the braided angle effect on the modalbehavior of 3D braided composites. According to the experimental parameters, a homogeneous model containing the interior,surface and corner representative unit cells of the braided composites were proposed to compute the elastic constants of eachcomposite. Besides, the fiber breakage defects were introduced to the homogeneous model to improve the accuracy ofpredicting the modal behavior of the braided composite. The results indicate that the increase of the braided angle and thefiber breakage defects could apparently reduce the natural frequency of the braided composite. The modal propertiessimulated by the homogeneous models containing some fiber breakage defects could fit well with the correspondingexperimental results. The proposed method to create the homogenous model can be used to predict the modal behavior of the3D braided composites.