Structural behavior of concentrically loaded GFRP-RPC circular columns

Abstract

The behavior of reinforced concrete (RC) members with glass fiber reinforced polymer (GFRP) bars has been the focus of several studies in previous years. However, a study to investigate the behavior of reactive powder concrete (RPC) columns reinforced with GFRP bars (GFRP-RPC) has not been conducted. This study aimed to study the structural behavior of circular columns fully reinforced with GFRP bars and hoops or spirals. In the present study, the behavior of GFRP-RPC circular columns under axial load is studied with the effect of four variables: longitudinal reinforcement ratio, transverse reinforcement ratio, transverse reinforcement configuration (hoops vs. spirals), and type of longitudinal reinforcement (GFRP, steel, and hybrid). Twenty circular columns with a diameter of 150 mm and a height of 1000 mm were cast and tested, divided into seven groups. Results discuss failure modes, axial load capacity, deformations (displacement and strains), and ductility. Test results indicate that the load capacity of the columns increased by ranging from approximately 46 to 56.25% when the longitudinal reinforcement ratio increased from 1.77 to 3.55%, also increased the transverse reinforcement ratio increased from 1.24 to 2.48%, enhancing the load capacity ranging from approximately 5.13 to 19.1%. Moreover, the nominal capacity of GFRP-RPC columns was compared with the design equations, so the results were verified.