Stretchability test of bra straps

The bra strap was taken as the research object.Taking the characteristics of the strap and its daily use into account,the breaking elongation test and constant rate elongation test were performed to test the stretchability of the strap samples.On the basis of the feature of stretch curve of the samples and the Meredith method,the yield point of fiber was determined,along with the effective elastic point of the samples.The paired sample test was used to detect the significant difference between the first and fifth stretch elastic recovery as well as plastic strain.The test result suggested that the stretch elastic recovery of the straps would deteriorate,while the plastic strain would increase in daily use.The analysis of variance and covariance were used to discuss the effect of fatigue elongation on the elastic recovery and plastic strain of the straps.The results indicated that the fatigue elongation of bra straps in normal daily use had little effect on the elastic recovery.