摘要
A representative volume element method and a novel mesomechanical-based polyline model are proposed to describe the misalignment of in-plane fibers induced by the insertion of stitch thread.A multi-scale mathematical model of in-plane elastic parameters for stitched composite laminate is established with ply-angle and stitch parameters as well as material parameters taken into account.Based on the fabrication of specimens and the verification of experimental platform,the superposition influences of stitch on structural anisotropy are revealed by the developed theoretical model.Results indicate that the stitch orientation can increase the structural anisotropy.The decreases of stitch pitch and spacing as well as the increase of thread diameter obviously reduce the elastic and shear moduli of laminates.Furthermore,the elastic and shear moduli as well as Poisson’s ratios show sinusoidal changes with a period of 90°as the ply-angle increases.The theoretical model not only analyzes the in-plane mechanical properties of stitched laminate with ply-angle,but also lays a foundation for the dynamic studies of stitched sandwich structures with ribs in the future.
作者
袁丽华
梁森
闫盛宇
YUAN Lihua;LIANG Sen;YAN Shengyu(School of Mechanical&Automotive Engineering,Qingdao University of Technology,Qingdao 266520,Shandong,China)
基金
National Natural Science Foundation of China(No.52075280)
Natural Science Foundation of Shandong province(No.ZR2019MEE088)。
