eva‎luation of Partially Steel-Jacketed (PSJ) RC columns using CDP model

9/18/2024 12:00:00 AM

In recent decades, the retrofitting of RC columns to enhance their load-bearing capacity has garnered significant attention. One of the common methods of retrofitting columns is to use a steel jacket with an angle and strips to increase the axial load capacity. The use of steel jacket is still an efficient solution due to its relatively low costs, ductile stress-strain behavior, simple and fast mounting with possible removing and reuse of the material. However, the design provisions for this application are still lack even if specific rules are necessary because the confinement effect can be strongly influenced by the amount and geometric configuration of the external steel. This thesis proposes a detailed 3D finite element model of reinforced concrete columns confined with external steel jackets using the ABAQUS software. The model is firstly validated on the available experimental obtaining a good agreement of the loading capacity. Finally, the model is used for considering the variation of the steel configuration in terms of strips number and thickness of the steel elements. in order to achieve optimal results. The retrofitted specimens with steel jacket show good ductility while improving loading capacity. The eva‎luation results indicate that increasing the number of strips in the studied specimens by keeping the amount of steel constant is significantly effective. Therefore the loading capacity of the specimens has increased between 5 and 14% compared to the laboratory-tested steel jacket specimen. Additionally, it is demonstrated that increasing the thickness of the steel strips has a negative effect on the behavior of the retrofitted columns. Moreover, the subsequent section of the study, has been shown that increasing the size of the strips in the sections near the heads of the steel jacket column at a fixed amount of steel prevents the plastic joint and the failure with a constant amount of steel, prevents plastic hinge formation and failure mode in this region.

مقاوم‌سازي , ژاكت فولادي , ستون بتن مسلح , محصورسازي , روش اجزاي محدود , آباكوس

retrofitting , steel jacket , RC columns , confinement , finite element model , ABAQUS

Danial Bateni

Dr. Gholamreza Ghodrati Amiri - Dr. Morteza Raissi Dehkordi