AID DJIHENEALLIAOUI MEROUABouafia Farida2026-10-142026-10-142026https://dspace.univ-temouchent.edu.dz/handle/123456789/7741This thesis focuses on the analysis of the mechanical behavior of pipelines, with particular emphasis on welded joints and their sensitivity to defects such as cracks. The main objective is to study the mechanisms of stress concentration and the fracture conditions in these critical zones, using an approach based on fracture mechanics and finite element numerical simulation (Abaqus).frPipelineswelded jointsfracture mechanicscracksstress concentrationstress intensity factor (K)fracture toughnessfinite element methodAbaqusnumerical analysis.Analyse numérique par la méthode des éléments finis (Abaqus) de la concentration des contraintes et du facteur d'intensité des contraintes au niveau des fissures dans les jonctions soudées des pipelinesThesis