Effects of Moisture Content on Variations in the Strength Properties of Pachyelasma Tessmannii and Chrysophyllum Delevayi Timbers

Abstract

Wood moisture content plays a crucial role in determining the strength properties of timber. This study investigates the effects of moisture content on the variations in the strength properties of Pachyelasma tessmannii (Ire) and Chrysophyllum delevayi (Osan) timbers species from Ilorin, North central Nigeria. The research aims to provide valuable insights into the relationship between moisture content and strength characteristics of these two timber species. A comprehensive literature review was conducted to gather existing knowledge on the topic. The research utilized wood samples from the two timber species, of which were subjected to controlled moisture content levels of 12%, 15% and 18%. The physical and various strength properties, including modulus of rupture (MOR), modulus of elasticity (MOE) and compression strength, were evaluated at different moisture content levels. The results indicated that both timber species exhibited a significant correlation between moisture content and strength properties. Higher moisture content was found to negatively impact the strength characteristics of the timbers. The results of the wood samples densities at 12% MC for each species were 904.20 Kg/m3 and 525.00 Kg/m3 respectively for Ire and Osan. At 12%, 15% and 18% MC, Ire has the highest MOE values of 5228.31 MPa, 7626.20 MPa and 8410.02 MPa respectively. At 15% and 18% MC, Ire has the highest MOR values of 126.90 KPa and 137.70 KPa respectively. At 12% MC, Osan has the highest MOR value of 58.28 KPa. At 12% MC, Osan and Ire had the same perpendicular compressive strength value of 15.0 KPa. At 15% and 18% MC, Ire has the highest perpendicular compressive strength values of 25.00 KPa and 27.50 KPa respectively. At 12%, 15% and 18% MC, Ire has the highest parallel compressive strength values of 50.76 KPa, 57.30 KPa and 57.5 KPa respectively.