The physical properties and strength characteristics of kenaf plants

This article reports some physical properties and strength characteristics of two kenaf (Hibiscus cannabinus) varieties in Nigeria at critical stages of harvest with a view of understanding the plant material reaction to the load and deformation. The kenaf samples were subjected to a uniaxial compression test between two parallel plates at a loading rate of 20 mm·min–1 and a uniaxial bending test between two supports on each end at a loading rate of 50 mm·min–1 using a Universal Instron Testing Machine (Instron, USA). The results of the parameters studied revealed that Tianung 1 gave the higher stem height, stem diameter, compressive stress, bending stress, rupture load, rupture energy, Young’s modulus, and toughness, which were 293.10 cm, 18.45 mm, 8.70 MPa, 44.86 MPa, 191.51 N, 3.43 J·mm–2, 350.81 MPa, and 6.85 N·mm–1, respectively, at four months after planting. The parameters studied significantly increased with maturity for the two kenaf varieties. However, the moisture content significantly reduced with maturity.