Behavior of concrete cylinders confined by a ferro-geopolymer jacket in axial compression

• Main Authors: Kothay Heng, Natthapong Areemit, Prinya Chindaprasirt
• Format: Article
• Language: English
• Published: Khon Kaen University 2017-06-01
• Series: Engineering and Applied Science Research
• Subjects: Ferro-geopolymer jacket; Compressive strength; Axial stiffness; Monolithic failure mode
• Online Access: https://www.tci-thaijo.org/index.php/easr/article/download/67564/67021

It is beneficial to utilize geopolymers for their potential properties to rehabilitate concrete structures. These properties include high adhesion to Ordinary Portland Cement (OPC) concrete even at low degrees of interfacial roughness, high durability and good fire resistance. This paper introduces use of a ferro-geopolymer jacket to strengthen concrete columns. It is a kind of jacket constructed with a geopolymer mortar reinforced with a wire mesh. This study was conducted to investigate the behavior of concrete cylinders confined with a ferro-geopolymer jacket in axial compression. OPC concrete cylinders with 100 mm diameter and 200 mm height were fabricated. High calcium fly ash-based geopolymer mortar, activated with sodium hydroxide (NaOH) and sodium silicate (Na2SiO3), cured at a temperature of 25 ºC was used. Ferro-geopolymer jackets with a25 mm thickness, were reinforced with 1, 2 and 3 layers of expanded metal mesh and cast around concrete cylinders. The study results revealed that the compressive load carrying capacity and axial stiffness of concrete cylinders were improved. A monolithic failure mode was obtained as a result of a strong adhesion between the geopolymer and the concrete core. Enhancement of compressive load carrying capacity of the jacketed concrete cylinders was caused by a combination of a confinement effect and the compressive load resistance of the jacket transferred from concrete core through bonding.