Strengthening of Recycled Aggregate Concrete Slender Column with CFRP

Abstract

This piece provides an overview of an experimental program that tests the structural performance of slender recycled aggregate RAC columns that are externally restrained by carbon fiber reinforced polymer (CFRP composite system). To demonstrate that the CFRP strengthening system is one of the recommended effective techniques for making up for the reduction in load-carrying capacity caused by the use of 100% RCA in combination with the slenderness of column specimens, eight slender circular RC columns were modeled and tested. To more accurately predict the structural features of the RC thin column (the ultimate carrying weight, first cracking load, load-displacement curve, and load-strain response), the findings from experiments have been analyzed and monitored. The findings indicated that the type of transverse reinforcement and the amount of external strengthening impact the degree of improvement in column performance. The strength for the tied RC columns with 100% RCA confined by (25, 50, and 100) % CFRP increased by 5.5, 44.97, and 112.85%, respectively, compared to control columns with no CFRP confinement. Similar strength improvements are seen in spirally RC columns with 100% RCA and the same external confinement coverage ratio: 10.32, 42.81, and 113.51%.

Keywords

• slender columns
• spiral reinforcement
• ties reinforcement
• cfrp confinement