Investigation of the physical and mechanical properties of Shea Tree timber (Vitellaria paradoxa) used for structural applications in Kwara State, Nigeria

Abstract

This study investigated the physical and mechanical properties of Shea Tree timber (V. paradoxa) for structural use obtained at different areas of Kwara State, Nigeria. Physical properties of the samples like moisture content, specific gravity and density was evaluated and the mechanical tests were tensile strength, modulus of rupture, modulus of elasticity, compression, shear and hardness. Results show that, the density of the specie varied from 1.05 to 1.48 (g/cm³), and specific gravity varied from 0.98 to 1.39. For the mechanical properties, the results revealed that at 18% moisture content and 80% grade stress, mean MOR of 28.91(N/mm²), mean MOE of 9,108 (N/mm²), compressive strength parallel to grain of 24.7 (N/mm²), compressive strength perpendicular to grain of 8.99 (N/mm²), shear strength of 2.01 (N/mm²), and tensile strength parallel to grain of 16.15 (N/mm²). Finally, according to BS 5268-2 (2002) the specie was characterised into strength classes between D50 and D70. The results obtained showed that Shea Tree is a hardwood and suitable to be used for structural engineering purposes.

Keywords: Vitellaria paradoxa, Physical properties, Mechanical properties, Structural timber, Green Construction