In this study, the reinforcing effect of recycled newsprint paper (RNP) in cement boards has been investigated.
The experimentaldesignconsistedoftwo variable factorsnamelyRNP andcalciumchloride (CaCl2).
In the sample preparation, boards with density of 0.7 kg/m3 were manufactured using fiber/cement ratios
of 10:90, 15:85 and 20:80 by weight and 3% and 5% CaCl2 as accelerator. Atleastfour boards (replications)
were fabricated for each treatment, and the mechanical and physical properties of the boards were evaluated.
The statistical analysis showed that the differences between the mean values of the RNP and CaCl2
contents among each of the groups (treatments) compared were significant. Test results showed that
addition of CaCl2 tends to enhance both the mechanical and physical properties of the boards. All properties
of the boards were improved when the CaCl2 content was increased from 3% to 5%. The rupture and
elasticity moduli of the boards decreased with an increase in the RNP content, and the maximum values
were obtained at RNP loading of 10%. The results also showed that as the fiber content was increased, significantincreased
in water absorption and thickness swelling occurred. Increasing RNP fiber contentfrom
10% to 20% reduced both the mechanical and physical properties considerably. The optimum condition
was obtained when the RNP and CaCl2 contents were 10% and 5%, respectively.