The results are reported of a comprehensive experimental investigation of the tensile behavior of twisted continuous- filament glass yarns. Existing theoretical treatments are reviewed and their compatability with the experimental results are examined. A physical model is proposed, based on a wrapped-ribbon twist geometry, which predicts both tensile modulus and tenacity of glass yarns as a function of the twist angle. The effect of filament bending strain on yarn tenacity has been included in the analysis. Excellent agreement between the model and the experimental results is shown.
