Aguwa, J.Characterization and Grading of South Eastern Nigeria grown Irvingia gabonensis Timber in Accordance with BS 5268

Abstract

The paper presents characterization and grading of South Eastern Nigeria grown Irvingia gabonensis timber in accordance with BS5268 (2002). Specimens used in the experiment were collected from a matured gabonensis in Akpugo forest, which were sliced into planks in green condition. The samples were seasoned naturally for six months and prepared according to British Standard BS 373 (1957) Methods of Testing Small Clear Specimen of Timber. The following laboratory test were carried out bending parallel to the grain, tension parallel to the grain, tension perpendicular to the grain, compression parallel to the grain, compression perpendicular to the grain, shear parallel to the grain, moisture content and density. The physical and mechanical properties of the timber specie, which were determined in the laboratory were adjusted to the values at moisture content of 12% in conformity with BS5268 (2002). The results were analysed statistically. Basic and grade stresses were computed using experimental failure stresses. The result of grade bending stress, density and mean modulus of elasticity showed that, Irvingia gabonensis can be graded and assigned to strength class D70. The timber is a strong, heavy hardwood and it is suitable for load bearing structures like railway sleepers and bridge beams