Microstructural, mechanical and statistical evaluation of concrete incorporating waste glass wool exposed to elevated temperatures

The purpose of this research was to determine the effects of using waste glass wool in concrete's on the concrete's mechanical properties. Samples of concrete containing varying percentages of waste glass wool by total concrete volume (0%, 1%, 2%, 3%, 4%, and 5%) were tested after exposure to a range of temperatures: 24 °C, 400 °C, 600 °C, and 800 °C. Several tests, including compressive strength (CS), splitting tensile strength (STS), and flexural strength (FS), were then performed on the samples in the laboratory following the completion of elevated temperature. The results showed that glass wool waste material reduces the concrete CS. Conversely, experiments have shown that samples STS and FS, increase proportionally with the amount of waste glass wool. Accordingly, the concrete compressive strength decreased by 4.26%, 7.84%, 11.87%, 14.24%, and 17.27% when the mixing ratio was increased from 1% to 5%. On the other hand, by increasing the mixing ratio from 1% to 5%, concrete STS and FS were enhanced by 9.61%; 15.19%; 27.70%; 36.58%; and 60.41% and 16.91%; 29.99%; 35.73%; 45.45%; and 59.45%, respectively. FE-SEM and EDX analysis was also included. Furthermore, equations were developed to estimate the capacities of concrete, with waste glass wool, after exposure to elevated temperatures. Taguchi analysis revealed that temperature is the most critical factor affecting mechanical performance, while the addition of waste glass wool contributed to strength retention at elevated temperatures. ANOVA confirmed the statistical significance of both temperature and waste glass wool's contribution, reinforcing their combined role in producing sustainable concrete with improved high-temperature resistance. The addition of waste glass wool to concrete recycles waste glass wool and minimizes the need for new raw materials and waste disposal requirements. According to the ratio and distribution above, adding modest quantities of glass wool may lighten concrete without affecting its strength.