tailieunhanh - Ebook Structure mechanics of woven fabrics: Part 2

Part 2 book "Structure mechanics of woven fabrics" presentation of content: The bending properties of woven fabrics, the shear properties of woven fabrics, fabric complex deformation analysis and simulation, mechanical properties of fabrics with seams, modelling drape deformation of woven fabrics and garments – theory,. Invite you to consult | 5 The bending properties of woven fabrics General bending behaviour of woven fabrics Introduction The bending properties of fabrics govern many aspects of fabric performance such as hand and drape and they are an essential part of the complex fabric deformation analysis. Thus the bending of woven fabrics has received considerable attention in the literature. Computational models for solving large-deflection elastic problems from theoretical models have been applied to specific fabric engineering and apparel industry problems for example the prediction of the robotic path for controlling the laying of fabric onto a work surface Brown et al. 1990 Clapp and Peng 1991 . The most detailed analyses of the bending behaviour of plain-weave fabrics were given by Abbott et al. 1973 de Jong and Postle 1977 Ghosh et al. 1990a b c Lloyd et al. 1978 and Hu et al. 1999 2000 . Modelling the bending of a woven fabric requires knowledge of the relationship between fabric bending rigidity the structural features of the fabric and the tensile bending properties of the constituent yarns measured empirically or determined through the properties of its constituent fibres and the yarn structure. It requires a large number of parameters and is very difficult to express in a closed form. Thus the applicability of such models is very limited. Konopasek 1980a proposed a cubic-spline-interpolation technique to represent the fabric moment-curvature relationship. Moment-curvature curve of bending behaviour Fabrics are very easy to bend. Their rigidity is usually less than 1 10 000 that of metal materials and about 1 100 that of tensile deformation. Bending properties of a fabric are determined by the yarn-bending behaviour the weave of the fabric and the finishing treatments applied. Yarn-bending behaviour in turn is determined by the mechanical properties of the constituent 123 124 Structure and mechanics of woven fabrics fibres and the structure of the yarn. The relationships .