Behavior of Aluminum Columns Enhanced with CFRP and Filled by Lightweight Concrete

Abstract

An experimental study of composite columns of hollow circular aluminum tubes enhanced with a fibers reinforced polymer (FRP) sheet and filled by lightweight concrete are presented in this paper. The study's scope is introducing and developing lightweight columns to be advantageous in lightweight and size limited structures. The test results discussed the influence of internal and external confinement effectiveness introduced by lightweight concrete and carbon fiber reinforced polymer (CFRP) retrofitting sheet, respectively. The column specimens were subjected to uniform axial compression load. Structural aluminum alloy circular hollow section has been used in this investigation. Carbon fiber reinforced polymer (CFRP) is used to piling aluminum tubes. Light weight expansion clay aggregate (LECA) is used to fabricate light weight concrete filling aluminum tubes. The strengths, shortening displacement, axial strains, lateral strains, and failure modes of columns were presented. The test results indicated that confinement and composite action between the constituent materials resulted in enhanced compressive strength, ductility and energy dissipation capacity of the proposed composite column. Finally, a simplified design equation is proposed to predict the compressive load capacity of this type of composite column.