Experimental analysis of the influence of stress concentrators on the buckling of woven materials under uniaxial tension

Woven textiles have ability to obtain spatial shape surfaces undergoing complex deformations. Formability of woven textile material is referred to shear deformations in macro scale when angle between two yarns systems are changed at crossover points. When form stability limit of sheet material are overstepped, complex deformations arises and the material buckles. This research analyses buckling phenomenon of deformed fabric during bias extension and uniaxial concentrated load tension. Image analysis method was adjusted to commit critical buckling parameters: critical load Pcr and critical elongation ecr. To obtain fabric buckling during common used uniaxial tension method it is possible only in bias direction, when concentrated load tension has shown that fabric buckles not only in bias direction but in principal directions (weft and warp) as well. The buckling takes place among intersections of distinct deformation zones between two stress concentrators and is related with the uniformity of deformation distribution in these zones.