Experimental study on various properties of sustainable, high-performance, and innovative composite (SIFGEO)

This paper focuses on sustainability and innovative materials in the construction industry. The study addresses the mechanical and high-temperature resistance (200 °C, 400 °C, and 600 °C) of SIFGEO, a superior composite material, by combining geopolymer concrete (GPC) and slurry-infiltrated fiber concrete (SIFCON) technologies. Within the scope of the study, the main binder in the SIFGEO specimens is blast furnace slag (BFS), and one group was produced only based on BFS. In the other groups, 10% were added by mass silica fume (SF), metakaolin (MK), and rice husk ash (RHA) instead of slag. As a result of the mechanical tests of the specimens that were not exposed to high temperatures, it was determined that the mixture containing only BFS as a binder had the highest compressive strength, flexural strength, and specific fracture energy. The compressive and flexural strengths of the mixture containing only BFS as a binder were 62.24 and 22.03 MPa, respectively, and the fracture energy was approximately 2146 N/m. The lowest results were obtained in the mixture where RHA was used as a partial replacement for BFS, with compressive strength, flexural strength, and fracture energy measured as 41.31 MPa, 16.81 MPa, and 1346.4 N/m, respectively. The compressive strength, flexural strength, and fracture energy of all mixtures showed a decreasing trend with increasing temperatures. It was observed that dense steel fibers provided effective crack control and increased ductility in both non-high temperature and high temperature exposed samples. In addition, depending on the parameters within the scope of the presented study, the correlation between the experimental results on SIFGEO samples was examined. In addition, statistical analyses were conducted to evaluate the relationships between the mechanical parameters. A strong correlation was found between flexural strength and fracture energy (R² values between 0.86 and 0.98) and between flexural strength and compressive strength (R² values between 0.89 and 0.96) for different binder types and temperature conditions. These results confirm that changes in flexural strength are closely linked to both fracture energy and compressive strength in SIFGEO specimens.