The strength of concrete structures deteriorates after exposure to fire. Strength loss varies with elevated temperature, fire duration, and the mechanical properties of concrete. Repairing and strengthening affected structures are important to improve their performances. Fire-damaged concrete has been repaired using fiber-reinforcing polymer. The superior properties of ultrahigh performance fiber-reinforced concrete (UHPFRC) make it suitable as a repair material. Furthermore, an excellent repair material should be able to bond properly with the substrate and maintain its structural integrity. The aim of this paper is to review the potential use of UHPFRRC as a repair material for fire-damaged concrete in terms of bond strength. Previous studies showed that developing efficient rehabilitation techniques that enable fire-damaged structures to be restored has some challenges. Whether UHPFRC can be used as a repair material particularly for fire-damaged concrete structure is recommended to be proven in future studies.
Purpose
This study aims to investigate and compare the interfacial bond characteristics between fire-damaged normal concrete substrate and ultra-high-performance fiber-reinforced concrete (UHPFRC) as a repair material.
Design/methodology/approach
First, fire-damaged normal concrete was prepared. Then, with a cast surface, the substrate was subjected to different surface moisture conditions. Three types of moisture conditions were set, namely, air dry, saturated surface dry (SSD) and wet. Slant shear and splitting cylinder tests were conducted to determine the interfacial bond strength of the composite.
Findings
In general, results indicate that surface moisture conditions significantly influence bond strength. The substrate under SSD condition exhibited the highest bond strength. The findings suggest that UHPFRC is a promising material for the repair and reuse of fire-damaged concrete structures.
Originality/value
This study compares the bond strength between fire-damaged normal concrete and UHPRC.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.