Experimental investigation of concentrically and eccentrically loaded circular hollow concrete columns reinforced with GFRP bars and spirals. (15th February 2023)

• Record Type: Journal Article
• Authors: Gouda, Mohammed Gamal; Mohamed, Hamdy M.; Manalo, Allan C.; Benmokrane, Brahim
• Is Part Of: Engineering structures. Volume 277(2023)
• Publication Date: 2023-02-15
• Subjects: Concrete -- Circular hollow columns -- Glass fiber-reinforced polymer (GFRP) reinforcement -- Longitudinal reinforcement ratio -- Eccentricity -- Interaction diagram -- Crack control -- First- and second-order effect; Structural engineering -- Periodicals; Structural analysis (Engineering) -- Periodicals; Construction, Technique de la -- Périodiques; Génie parasismique -- Périodiques; Pression du vent -- Périodiques; Earthquake engineering; Structural engineering; Wind-pressure; Periodicals; 624.105
• DOI: 10.1016/j.engstruct.2022.115442
• Languages: English
• ISSNs: 0141-0296

Abstract

Highlights: Concentric Behavior of Hollow RC Columns with GFRP Bars and Spirals. Eccentric Behavior of Hollow RC Columns with GFRP Bars and Spirals. Ductility of Hollow RC Columns with GFRP Bars and Spirals. Effect of GFRP Longitudinal Reinforcement Ratio on Failure Mechanisms and Ultimate Axial–Flexural Capacity of Hollow RC Columns. Abstract: Hollow concrete columns (HCCs) constitute a structural system with low self-weight, reduced material use, and high strength-to-weight ratio. Limited studies, however, have focused on investigating the concentrically loaded behavior of circular HCCs reinforced with glass fiber-reinforced polymer (GFRP) reinforcement. Moreover, there appears to be no research on the behavior of such columns under eccentric loading. This study investigated the performance of 10 large-scale GFRP-reinforced HCCs measuring 1, 500 mm in height with outer/inner diameters of 305/113 mm. The test parameters were the effect of two longitudinal reinforcement ratios (2.5 % and 3.8 %) and five different levels of eccentricity (0 %, 8.2 %, 16.4 %, 32.8 %, and 65.6 % eccentricity) on the compressive and flexural behavior of GFRP-reinforced circular hollow columns. The test results show that the behavior of these columns was more significantly affected by the level of applied eccentricity than the longitudinal reinforcement ratio. The failure of specimens loaded under low eccentricity levels was compression controlled due to spalling of the concrete cover, followed by fracturing of the GFRP bars, attributed to most of the cross section being subjected to high compressive stresses. Conversely, initiation of failure for the specimens tested under high eccentricity levels was flexural tension followed by tensile cracking, which caused a secondary compression failure in the concrete. It should be noted that the contribution of the second-order effect on the total moment capacity was minor, approximately 9 %, compared to the primary bending moment induced by the initial eccentricity of 91 % on average. Lastly, the ductility of the hollow GFRP-reinforced concrete columns was higher than that of solid columns under eccentric loading, which significantly improved the energy absorption ability, leading to a decrease in the strength decay beyond the peak load.