Effect of sand addition on properties of fiber-reinforced cement composites

The effect of sand addition on the mechanical properties of cast and extrud ed polyvinyl acetate fiber-reinforced cement composites was investigated. T he addition of sane increased the strength of the plain cement paste, but d ecreased the mechanical performance of the fiber-reinforced cement composit es. To understand the behavior of the composites, microstructural propertie s such as fiber dispersion, alignment, and composite porosity were investig ated and statistically quantified. The reduction in the performance of the composites with sand was found to be a result of the differences in fiber d ispersion, composite porosity, and interaction between the fiber and the ma trix. Fiber clumping, increase in the size and number of fiber-free areas, and higher matrix porosity were observed in the composites when sand was us ed.