Strength and water absorption characteristics of cement-bonded particleboard produced from coconut husk

Abstract

Wood-Cement composites were produced from coconut (Cocos nucifera) husk, an agricultural residue with minimal economic utilization in Nigeria. Contrary to conventional practice, the boards were fabricated in the laboratory without external pressure application. The effects of calcium chloride (CaCl2) addition on the hardening time, appearance, bending and compressive strength, and water absorption properties of the boards were also investigated. The boards had a relatively low density with values ranging from about 594 to 650 Kg/m3. The addition of CaCl2 reduced the hardening time of the board by about 50% (from 36 to 12 hours) and also imparted glossiness in the treated boards. The Modulus of Elasticity (MOE) and Modulus of Rupture (MOR) of the untreated boards (677 N/mm2 and 1.25 N/mm2 respectively) were slightly lower than those of the treated boards (1104 N/mm2 and 1.48 N/mm2 respectively). The mean compressive strength of the CaCl2–treated boards (3.68 N/mm2) was also slightly higher than that of the untreated boards (3.39 N/mm2). However, the observed differences were not significant. The rate of water absorption (< 25% after 24 hours) and the resultant thickness swelling (<1% after 24 hours) of the boards was relatively slow. It was concluded that the material could be used in bearing wall construction and as partitioning in bungalows and one- storey buildings in Nigeria.

Journal of Civil Engineering Research and Practice Vol. 3(1) 2006: 41-49