Strength and some Physical Properties of Allanblackia Parviflora for Furniture Production in Ghana

Abstract

In Ghana, many of our traditional wood species are over exploited and threatened to extinction. The utilization of other lesser-used and lesser known wood species needs to be looked at urgently as a possibility of increasing the wood resource base. And a successful expansion of the resource base is dependent on adequate knowledge of the properties of the lesser-used species such as Allanblackia parviflora which can be a good substitute to some of the dwindling species. It was against this background that the strength and some physical properties of Allanblackia parviflora trees were determined to predict the suitability of the species for furniture production and structural raw material for downstream processing of wood products. Three Allanblackia parviflora trees were used for the study. The main statistical tools used were descriptive statistics and one-way analysis of variance (ANOVA). Mechanical strength test specimens were prepared and tested in accordance with the British Standard BS 373: 1957. Mean green moisture content was 81.19%. Mean basic density was 539.00kg/m3. The range of mean strength values in N/mm2 in the ‘green’ and dry (12 % M.C) conditions for the three wood species were as follows: Modulus of Rupture: 50.00 - 56.00 (85.00 - 94.00), Modulus of Elasticity: 6,387.00 - 6,951.00 (8,287.00 - 8,875.00), compression parallel to grain: 24.00 - 28.00 (13.00 - 14.00) and shear parallel to grain 6.83 - 7.74 (9.62 - 10.82). Mean ratios of dry to ‘green’ MOR and MOE were 1.68 and 1.28. Almost all strength tests conducted showed a consistent trend that, the heartwood portion of each division was slightly stronger in terms of resistance to failure than its corresponding sapwood portion. Comparing the strength of Allanblackia parviflora to an existing classification (grade), strength is ‘medium’ in Allanblackia parviflora tree wood. It compared favourably with known species such as Aningeria altissima, Terminaria ivorensis, and Antiaris toxicaria in several properties and strength which are suitable for furniture production