Glued Laminated Timber from Oil Palm Timber – Beam Structure, Production and Elastomechanical Properties

Abstract

AbstractOil palm timber used for load-bearing purposes such as glued laminated timber (GLT) needs to have clearly defined strength and stiffness values. Because the wood density (which correlates to elastomechanical properties) varies significantly within oil palm trunks, oil palm boards must be graded based on their density across the board width in order to homogenize and improve the properties of the final product. In this preliminary investigation, 20 beams of combined GLT with four different types of graded lamellas were produced and tested in a 4-point-bending test. The results show a correlation between density and bending strength. The characteristic strength values are achieved, and the elastomechanical properties of beams based on lamellas that are ripped lengthwise and edge-glued according to their density are higher compared to beams based on lamellas cut only according to their geometry. A correlation between bending strength and local MOE is determined. In summary, lengthwise ripping of oil palm boards according to their density across the board width as well as a grading according to density limit values is shown to improve the properties of combined GLT made from oil palm timber for load-bearing purposes.KeywordsGLTOil palm timberDensityGLT productionPropertiesBuilding products