Thermally treated granite slurry waste as a mitigating agent for sisal fiber mineralization in fiber-cement composites

Abstract

This study explores the use of thermally treated granite slurry waste to mitigate the mineralization of sisal fibers in fiber-cement composites. Granite waste was thermally treated at 600°C and 900°C, and the treated materials were analyzed using X-ray fluorescence (XRF), Fourier transform infrared spectroscopy (FTIR), and thermogravimetric analysis (TGA). Sisal fibers, alkali-treated with 1.7% NaOH, were incorporated into fiber-cement composites, where 15% and 30% of the cement was replaced by treated and untreated granite. Composites with 15% of granite treated at 600°C and 900°C showed improvements in compressive strength of up to 12% and 18%, respectively, compared to the control. The flexural strength increased by 10% with 15% granite treated at 900°C. However, the untreated granite at 30% replacement increased porosity by 25% and water absorption by 18%, negatively affecting the mechanical properties. Aging tests showed a 40% loss in compressive strength, while composites with 30% granite treated at 900°C maintained their flexural strength, making them more durable. These findings highlight the potential of thermally treated granite waste to enhance the sustainability and performance of fiber-cement composites in construction.