Effect of nano-silica and bagasee fibers on bending strength and physical properties of cement fiberboards

In this research, the properties of cement fiberboard produced using different contents of nano-silica and bleached bagasse fibers were evaluated. Different ratios of bagasse fibers, cement and nano-silica were blended using an electrical blender. The mixture was then poured into a mould (15x18x18 cm dimension). The produced mould samples were matured for 14 days at room temperature and high moisture content (100%) and after maturing, the bending strength and physical properties of boards were measured. Results showed that both materials (naosilica and bagasse fibers) changed the bending and physical properties of the final boards. The bending strength of samples increased with the increase in nano-silica up to 1% and exceeding 1% decreased this property. It is because high content of silica (more than 1%) results in aggregate of nano-silica and cement and micro cracks occurred in samples. Also the increase in bagasse fiber up to 4% increased of bending strength of boards and more bagasse fibers decreased the bending strength. It is because high bagasse fibers cannot distribute in the cement matrix and fiber bundles reduced the bending strength. However, as the nano-silica and bagasse fibers content increase, the water and moisture absorption as well as thickness swelling increases, whereas density decreases.