Title:
Geopolymer Composites: Potential as Repair and Strengthening Materials for Concrete Structures
Author(s):
Giwan Noh, Uksun Kim, Myoungsu Shin, Woo-Young Lim, and Thomas H.-K. Kang
Publication:
Structural Journal
Volume:
122
Issue:
5
Appears on pages(s):
165-179
Keywords:
bond strength; geopolymer; geopolymer concrete; rehabilitation; repair; strengthening
DOI:
10.14359/51746719
Date:
9/1/2025
Abstract:
Geopolymer, an inorganic polymer material, has recently gained attention as an eco-friendly alternative to portland cement. Numerous studies have explored the potential of geopolymer as a primary structural material. This study aimed to examine the efficacy of geopolymer composites as repairing and strengthening materials rather than as structural materials. Data from 782 bond strength tests and 164 structural tests were collected and analyzed, including those on beams, beam-column connections, and walls. The analysis focused on critical factors affecting the bond strength of geopolymer composites with conventional cementitious concrete, and the structural behaviors of reinforced concrete members repaired or strengthened with these composites. The findings highlight the potential of geopolymer composites for enhancing the resilience and toughness of existing damaged or undamaged concrete structures. Additionally, they offer valuable insights into the key considerations for using geopolymer composites as repair or strengthening materials, providing a useful reference for future research in this field.
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