An improved analysis of bagging of textile fabrics. Part II: experimental work

Abstract

PurposeAims to analyse the stress distribution in a circular flexible sheet. Part II verifies the theory with experimental work.Design/methodology/approachThe investigation includes analysing the stress distribution in a circular flexible sheet clamped around its circumference under an externally applied force by a spherical object. Movement of the material normal to its original plane is then related to the external force and the elastic properties of the sheet, i.e. the elastic modulus and the Poisson's ratio. The effects of the size of the force‐applying object, relative to the sample radius, are also investigated.FindingsThe relationship between the applied force on the centre of a flexible sheet material by a spherical object and the sag of the sheet was derived. Poisson's ratio has an important role on the mechanism of deformation, restricting the extension of the sheet when it is high and intensifying the discontinuity of the strain at the interface.Research limitations/implicationsThe work could be expanded to industrial fabrics and to composite materials.Practical implicationsThe two papers provide a first step in an attempt for a better understanding of the stresses involved in bagging of a linear elastic sheet. They provide the basis for the development of fabrics that can withstand bagging problems. This research may also put forward improved methods of measuring bagginess. Some of the theoretical work may be used to predict bagginess of fabrics based on properties.Originality/valueThe paper has two improvements on previous work: the inclusion of the effect of fabric Poisson ratio, and the suggestion of a better method of calculating the overall anisotropic properties.