Strain measurements on soft materials application to cloth and papers

摘要

Abstract: We present a nondestructive and noncontact extensometrytechnique, which has been developed in order to studythe behavior of different materials such aspolycarbonate, araldite, and urethane. The aim of thisarticle is to propose an original extensometrytechnique applied to textiles and papers. A spectralanalysis of a cross grating marked on the surface of aspecimen and recorded by a CCD camera is presented. Theprocedure is based on the use of a bidimensional FFTalgorithm coupled with an interpolation process. Itleads to the accurate determination of frequencies.Numerical simulations indicate that the strainsensitivity is of the same order as the sensitivitygiven by a strain gage technique.!17