Variations in Wood Anatomical Characteristics of Nigerian grown Triplochiton scleroxylon and their Relationships with Selected Mechanical Properties

Abstract

Anatomical characteristics of wood of 27-year old Triplochiton scleroxylon(obeche) were investigated to assess the variation pattern of fibre, vessel and ray elements. Test samples were obtained axially from butt, 10%, 30%, 50%, 70% and 90% of merchantable height (MH); and radially from inner wood, middle wood and outer wood. Results show that fibre proportion ranged from 53.5% at 90% of MH to 64.7% at the butt. Vessel proportion ranged from 18.85 to 17.1%, while ray proportion had a range of between 16.7% and 26.6%. Axial variation for fibre and vessels were significant at 5% level that of while those of rays were not significant. It was further revealed that variations of fibre diameter and fibre wall thickness generally increased from butt to top of tree, lumen width and fibre length varied inconsistently along the bole. Modulus of Elasticity
MOE was the most predictable Strength property, while Impact Bending IMB was least
predictable. Addition of fibre proportion to selected fibre dimensional characteristics improved predictability in strength properties except in Maximum compressive strength parallel to grain MCS//.

Keywords: Triplochiton scleroxylon, Anatomical properties Strength properties, Omo Forest Reserve, Nigeria

Journal of Applied Science, Engineering and Technology Vol. 6 (1) 2006 pp. 68-75