Bond failure of corroded rebar embedded in rubberized geopolymer concrete: Experimental evaluation

作者：Fangduo Xiao, Qiang Li, Shiwei Lu, Pengfei Liu, Junlong Yang, Zhihang Xue, Shikun Chen, Dongming Yan · 发表于：Construction and Building Materials · 年份：2026 · DOI：10.1016/j.conbuildmat.2026.145922 · 被引用次数：2 · 研究领域：Innovative concrete reinforcement materials、Concrete Corrosion and Durability、Structural Behavior of Reinforced Concrete

Reinforcement corrosion significantly limits the interfacial bond behavior of reinforced concrete (RC) structures in harsh environments. Developing concrete materials with erosion resistance and high toughness is critical for improving structural durability. Therefore, a total of 96 central pull-out specimens were tested to systematically investigate the combined effects among corrosion, geopolymer concrete type, and rubber replacement ratio on the bond behavior. The test results show that slag-based geopolymer (SG) specimens tend to crack, leading to the significant corrosion of internal steel bar, and no apparent enhancement in bond strength compared with that of ordinary Portland cement (OPC) specimens. Metakaolin-based geopolymer (MKG) specimens present a 37.5% higher bond strength than OPC in the uncorroded state. However, they demonstrate a pronounced sensitivity to corrosion, leading to a 31.6% reduction in bond strength. The water-repellency of hydrophobic metakaolin-based geopolymer (HMKG) alleviates the steel corrosion and results in a high bond strength retention of 80.8% under erosion conditions. The incorporation of rubber effectively enhances the toughness for all types of geopolymer concrete, which suppresses the corrosion-induced cracks and thereby improves durability and deformation capacity of interface. However, the compressive strength of the concrete decreases by 6.7–51.8% with rubber replacement ratio increasing, which aggravates the bond strength deteri...