针织物沿织层方向拉伸时的不屈曲性

Non-Existence of Buckling of Knitted Fabric Under Tension Along Course Direction

针织物在受到拉伸时通常会屈曲,但当受到沿织层向拉伸时不发生屈曲,基于针织物的细观本构模型,给出了该不屈曲性的严格证明,证明中考虑了针织物在临界状态的大变形,使用了严格的三维不稳定性理论以避免薄板理论近似可能引起的偏差.针织物片被看作三维物体,其所有的边界条件皆被满足.研究证明,两种可能的屈曲模态(弯曲模态和桶形模态,即针织物受非织层方向拉伸时的可能屈曲模态)对受织层方向拉伸的针织物都不会发生.

It is usual for knitted fabric to buckle under tension, but it doesn＇t buckle when it is subjected to tension along course direction. Based on the micro-mechanical model of knitted fabric, the non-existence of buckling was proved, and the large deformation of knitted fabric in possibly critical configuration was taken into consideration. The rigid three-dimensional theory of instability was used to avoid possible deviation from the approximation of the theory of thin plate. The fabric sheet was considered as a three-dimensional body and all the boundary conditions were satisfied. It is shown that the two possible buckling modes （flexural mode and barreling mode） don＇t occur for the knitted fabric sheet subjected to tension along course direction.