Anas Nahidh Hassooni
Salah R. Al-Zaidee

Concrete Filled Double Steel Tube (CFDST) columns are a modern technique of composite structural element that has fire resistance and has been adopted in high-rise building structures. The Concrete Filled Steel Tube (CFST) columns also have high strength and ductility due to composite action. This type of column CFST can sustain a heavy load with high performance and has been adopted in recent years in many countries around the world. The aim of the present work is to study the behavior and strength of rehabilitation of composite columns that are made from concrete core and surrounded steel tubes under the effect of axial compression loads with different height to diameter ratios such as ۵.۴۶, ۱۰.۹۱, and ۱۶.۳۷, respectively, by experimental tests. Double skin methodology is adopted to repair the damaged columns that were tested up to ۸۵% of the ultimate load. Strength column capacity of double skin columns, axial and buckling deformations with axial and buckling strains are investigated. Test results showed that the repaired specimens up to ۸۵% of the ultimate load had the same strength carrying capacity as compared with the control specimens, which had the same geometry. The ductility of an ۸۰۰ mm specimen’s height is greater than the other tested specimens, while the stiffness of short specimens becomes high. Doi: ۱۰.۲۸۹۹۱/CEJ-۲۰۲۲-۰۸-۰۳-۰۱۳ Full Text: PDF

Double Skin Column; Composite Column; CFST; CFDST; Ductility.