Reinforcing effects of gypsum composite with basalt fiber and diatomite for improvement of high-temperature endurance

In this study, plaster materials composed of gypsum, basalt fiber (BF), and diatomite additives were produced, and the combined effects of high-temperature-resistant BF and porous, lightweight siliceous diatomite on the thermal and mechanical endurance of the resulting composite at high temperatures were studied. At room temperature, the incorporation of 0.5 wt% BF improved the bending and compressive strength by 43% and 16%, respectively, which showed a better improvement than the 1 wt% BF incorporation, with the respective numbers of 8% and 7%. The reinforcing effect of BF is discernible at elevated temperatures; however, the reinforcing effect is lost up to 600 celcius due to fiber failure. Diatomite significantly alleviated the formation and propagation of cracks in the gypsum composite at high temperatures by forming a porous structure that created pathways for releasing internal vapor pressure at high temperatures. The thermal conductivity values decreased from 0.411 to 0.364 W/ mk as the diatomite content increased to 20 wt%, however, the polar surface energy of BF modified the growth of the gypsum crystals, resulting in an increased thermal conductivity of the composite. Furthermore, changes occurring in the morphology and chemical composition of the gypsum composite following heat-treatment were analyzed by the differential scanning calorimetry, X-ray diffraction, and scanning electron microscope. The results obtained validate the usage of BF and diatomite as potential additives for improving the performance of gypsum composites as fire protection materials in building construction.

Automated summary

The study demonstrated that BF and diatomite as additives can significantly improve the performance of gypsum composites at high temperatures, enhancing bending and compressive strength. While the reinforcing effect of BF is observable, it diminishes at high temperatures, and diatomite helps slow down crack formation and propagation.