Mechanical Properties of Selected Indigenous Timber Species from Southwestern Nigeria: A Comparative Study for Structural Applications

Abstract

The demand for sustainable and cost-effective construction materials in Nigeria has renewed interest in the structural use of indigenous timber species. However, the absence of standardized mechanical data on many local timbers has limited their acceptance in structural applications, often resulting in reliance on traditional knowledge rather than empirical evidence. This study investigates the mechanical properties of four indigenous timber species from Southwestern Nigeria—Anogeissus leiocarpus (Ayin), Albizia ferruginea (Alakrity), Pterocarpus erinaceus (Ayere), and Ricinodendron heudelotii (Eru)—to evaluate their suitability for structural use. Standard laboratory tests were conducted to determine the modulus of rupture (MOR) and modulus of elasticity (MOE) under both wet and oven-dried conditions using uniformly dimensioned specimens. The results revealed significant differences in strength and stiffness among the species. In the oven-dried condition, Anogeissus leiocarpus recorded the highest MOR of 3.1 MPa, outperforming Albizia ferruginea by 22.6%, Ricinodendron heudelotii by 9.7%, and Pterocarpus erinaceus by 38.7%. Similarly, in MOE, Anogeissus leiocarpus showed the highest value of 50.8 MPa, exceeding Albizia ferruginea by 2.6%, Ricinodendron heudelotii by 5.5%, and Pterocarpus erinaceus by 7.9%. Across all species, oven-dried samples consistently exhibited superior mechanical performance compared to wet samples. These findings provide critical comparative data to inform material selection in construction and promote the effective utilization of indigenous timber resources. The study contributes to advancing sustainable construction practices in Nigeria by encouraging reliance on locally sourced materials, reducing dependence on imported timber, and supporting environmentally responsible building solutions.