CARBON DIOXIDE INJECTION IN BAMBOO CEMENT BOARD PRODUCTION

The objective of this study was to evaluate the effect of the incorporation of injection of CO2 in liquid phase at 30 minutes of curing time period to the physical and mechanical properties of cement board made from bamboo culm particles of Gigantochloa atter, Dendrocalamus asper and Schizostachyium brachycla. Mixtures of bamboo culm particles, cement, and water on the ratio by weight of 1 : 2.5 : 1.25 were casted in iron plate mold of 25 x 25 x 1 cm3, pressed and then hold for 24 hours to obtain the targeted density of cement board samples of 1 g cm-3. Samples were cut in accordance with the size of physical and mechanical testing of and then injected by CO2 in liquid phase at 30 minutes of curing time period. Samples of cement board were tested for physical and mechanical properties according to Japanese Industrial Standard (JIS) A 5417-1992. Results showed that the physical properties consisted of moisture content of the boards ranging from 3.15% to 3.62%, density from 0.68 g cm-3 to 0.80 g cm-3, water absorption for 24 hours from 45.11% to 57.60%, and thickness swelling for 24 hours from 0.65% to 0.87%. Mechanical properties consisted of internal bond ranging from 0.18 kg cm-2 to 0.74 kg cm-2, MOE from 1339.03 kg cm-2 to 5030.50 kg cm-2 and MOR from 40.12 kg cm-2 to 79.59 kg cm-2. Only cement board made from mixture of Gigantochloa atter particles, Portland cement and water met physical properties requirement of JIS A 5417-1992 and no cement board satisfied mechanical properties requirement of JIS A 5417-1992