Soutenance de thèse de Kablan Guy-Delphin Agniman

Textile plies used in the tire industry are unidirectional composite materials consisting of polymer reinforcements embedded in a rubber matrix. Under certain service conditions, these plies are subjected to axial compression, which can be damaging to the reinforcements. In this context, the present study focuses on the axial compressive behavior of rubberized textile reinforcements. The objectives of this work are to analyze the deformation mechanisms of rubberized textile cords under axial compressive loading, to evaluate the contribution of the cord to the global axial compressive stiffness of the composite, and to study the influence of cord architectural parameters on these two aspects. To achieve these objectives, three analysis tools were developed. The first is a quasi-static compression test protocol for rubberized textile composites, which made it possible to reliably evaluate the contribution of the cord to the overall axial compressive stiffness of the composite. The second is an in situ compression test protocol inside a tomograph, along with the associated image analyses, which enabled a quantitative analysis of the cord kinematics within the rubber. Finally, the third tool is a filament-scale numerical simulation using the finite element code Multifil, which provided further insight into the deformation mechanisms at this scale. The combined use of these tools has made it possible to quantify the contribution of textile cables to the axial compressive stiffness of the rubber-cable composite, to reveal the deformation mechanisms by which textile reinforcements in a rubber matrix respond to axial compressive loading of the composite, and to highlight instabilities and damage to the cables that may result from the axial compression of the composite. Furthermore, the impact of certain architectural and process parameters on the cable’s longitudinal compressive behaviour was investigated. The parameters investigated were : the type of rubber, the twist ratio, the presence of adhesive, the curing tension and the processing tension.

Composition du jury : 

• Yann MARCO Professeur des universités, ENSTA | Institut Polytechnique de Paris, Président
• Eric MAIRE Directeur de recherche CNRS, INSA de Lyon, Rapporteur & Examinateur
• Nahiene HAMILA Professeur des universités, Bretagne INP – IRDL, Rapporteur & Examinateur
• Audrey HIVET Maitresse de conférence, Université d’Orléans, Examinatrice