Modeling of the cyclic visco-elasto-plastic one-dimensional behavior of polyamide-based woven straps

Abstract

This study focuses on modeling the mechanical behavior of threadlike woven materials or those shaped in uniaxial form, such as wires, ropes, woven lines, cables, straps, slings, etc. The proposed one-dimensional model is based on the superimposition of two stress contributions: a non-Newtonian visco-elastic stress and a time-independent stress. The time-independent stress represents a particular irreversible behavior, linked to the loading history. This model neglects the thickness of the time-independent hysteresis loops during the unloading–reloading processes while preserving the irreversible character of elasto-plastic-type behavior. The model's predictions are compared to a set of experimental results, carried out on polyamide 6-6 straps, available from previous experimental studies in the literature. The model describes the shape of the stress–strain hysteresis loops very well and predicts perfectly the direction of the strain and stress evolutions during the creep and relaxation periods, regardless of their position in the first load or in the load–unload branches.