Nonlinear tensile behavior of cotton fabric reinforced polypropylene composites

From the perspectives of elastoplasticity (nontime-dependent) and viscoelasticity (time-dependent), the Ramberg-Osgood relation and time-varying viscosity Maxwell (TVM) models were used to model and analyze the stress-strain behavior of cotton fabric-reinforced polypropylene composites (CFRLs), respectively. The Ramberg-Osgood relation could well describe the tensile behavior of CFRLs as an elastoplastic behavior, while the tensile behavior could also be described as a nonlinear viscoelasticity behavior by Maxwell model. The fitting results showed that the Maxwell model accurately described the tensile behavior of different CFRLs samples under low strain, but there was a considerable gap between the test data and model values when the strain was greater than 5%. Therefore, a time-varying viscosity fluid damper was used instead of a Newtonian fluid damper to modify the Maxwell model, namely the TVM model. The TVM model closely described the stress-strain behavior during the entire tensile process.

Automated summary

This study utilized the Ramberg-Osgood relation and Maxwell model to analyze the stress-strain behavior of CFRLs, finding that the Maxwell model accurately described CFRLs' tensile behavior at low strain but had discrepancies at strains above 5%. To address this, a TVM model with time-varying viscosity was introduced to better describe the entire tensile process of CFRLs.