The aim of this work was to study the effect of induced mass irregularities of yarn on
the strain monitoring of fabric during a tensile test. Slub yarns with different induced mass
irregularities were produced and used as weft yarns in plain woven fabric. The Digital Im- age Correlation (DIC) method was used to evaluate the strain distribution map of the fabric
during the tensile test. Images of the reference sample as well as of the strained fabric
under the sequential strain applied were captured. By applying the DIC method, a strain
distribution map of the fabric at a certain value of the strain applied was calculated for all
samples. Results of the strain map calculated were then compared with the image of the ac- tual fabric. It was found that there was good agreement between the map of strain distribution calculated by DIC and the local concentration of strain in the fabric. The results also
revealed that the variation in strain distribution in the fabric during the tensile test was
correlated exponentially to the breaking stress in cN/tex) of yarn as well as the breaking
strength in N of the fabric.