Analysis of a quasi-three-point bending test for fabrics with friction and extensibility effect

Abstract

This paper presents a theoretical bending model to investigate the quasi-three-point bending step of the comprehensive handle evaluation system for fabrics and yarns (CHES-FY). The effect of the friction and extensibility of fabrics on the bending step of the CHES-FY is discussed based on the theoretical bending model in three cases, and bending parameters, including maximum bending force, linear fitting slope and bending work, are featured from the bending force–displacement curves of each case. Comparisons of the theoretical and experimental results were also conducted to validate the model. The results revealed that the friction effect tended to enhance the bending parameters of the bending force–displacement curve of the bending step, and the effect of the friction could be remarkable at low bending rigidity of samples. However, the effect of the extensibility of samples was almost negligible for the bending test of wear fabrics, as the maximal relative error was less than 11.7% for fabrics where the tensile elastic constant was higher than 0.1 N/cm·%. This work can also provide a theoretical guidance for improving the measurement accuracy of the three-point bending test.