THE PERFORMANCE OF SUPERABSORBENT POLYMER BEADS ON FIBER REINFORCED SELF-COMPACTING CONCRETE EXPOSED TO FIRE FLAME

Abstract

Concrete structures, particularly self-compacting concrete (SCC), are highly vulnerable to elevated temperatures, which can lead to strength degradation, cracking, and explosive spalling. Improving the fire resistance and residual performance of SCC remains a significant challenge in construction engineering. Therefore, this study aims to investigate the effectiveness of Superabsorbent Polymer (SAP) beads in enhancing the performance of basalt fiber-reinforced SCC under fire exposure. An experimental program was conducted using four SCC mixtures with a constant basalt fiber content and varying SAP dosages of 0%, 3%, 4%, and 5% by weight of cementitious materials. The fresh properties were evaluated using slump flow, T500, V-funnel, and L-box tests, while mechanical properties were assessed through compressive, tensile, and flexural strength tests. Specimens were then exposed to elevated temperatures of 300°C, 500°C, and 700°C to evaluate residual performance. The results showed that SAP incorporation improved workability but reduced early-age strength due to increased porosity. However, at later ages, internal curing enhanced hydration and strength development. After fire exposure, SAP-modified mixes exhibited significantly improved residual strength compared to the control mix, with the 5% SAP mixture showing the best performance due to reduced vapor pressure and minimized spalling. In conclusion, the combined use of SAP beads and basalt fibers effectively enhances the fire resistance and long-term performance of SCC, making it suitable for high-temperature applications.