EFFECTS OF WOOD:CEMENT RATIO ON MECHANICAL AND PHYSICAL PROPERTIES OF THREE-LAYERED CEMENT-BONDED PARTICLEBOARDS FROM LEUCAENA LEUCOCEPHALA

Three-layered cement-bonded particleboards (CBPs) from 8- and 16-year-old Leucaena leucocephala trees were manufactured in the laboratory and examined for suitability as a construction material. Four wood–cement ratios, i.e. 1:1.75, 1:2.0, 1:2.25 and 1:2.5 were used. A combination of aluminium sulphate and sodium silicate was used as cement accelerator. Wood particles retained at 2 mm sieve size were used for the core layer and a combination of 1 and 0.5 mm were used for the outer layers. The mechanical and physical properties of the boards were evaluated based on MS 544: 2001. The modulus of rupture ranged from 7.68 to11.22 MPa and modulus of elasticity, 2981 to 4002 MPa. The internal bond ranged from 0.59 to 0.90 MPa. The water absorption and thickness swelling after 24 hours soaking in water ranged from 12.42 to 19.04% and 0.38 to 0.70% respectively. Generally, the CBPs produced from 8-year-old trees gave better mechanical strength than the 16-year-olds.