Structural-Sized Compression Grade Stresses Derived from Malaysian Tropical Hardwood Timber

Strength properties of Malaysian timbers are given in MS 544: Part 2. However, the strength properties specified in MS 544: Part 2 was derived from the assessment of small clear specimen. In recent decades, there has been a significant and swift progression in the evolution of engineered timber products (ETP), accompanied by a substantial increase in their utilization within the construction industry. Therefore, to provide a reliable design for engineered timber product, it is essential to have the access to the strength properties derived from structural timber size. Thus, the aim of this study was to assess the compressive properties (parallel and perpendicular to the grain) of Malaysian tropical hardwoods utilising structurally sized specimens. The timber species tested ranged in strength group (SG) 1 until 7 in accordance with MS 544: Part 2 namely Balau, Kempas, Kelat, Resak, Kapur, Keruing, Mengkulang, Light Red Meranti and Geronggang. Based on EN 408:2012, the desired properties (compressive strength and modulus of elasticity) were determined for the timber specimens. According to the results of this study, Kempas (SG2) and Resak (SG4) have the highest compressive strength parallel (62.9 N/mm2) and perpendicular (17.7 N/mm2 ) to the grain, respectively. In contrast, Geronggang (SG7) and Light Red Meranti (SG6) shows the weakest compressive strength parallelly (26.9 N/mm2 ) and perpendicularly (3.3 N/mm2) respectively. Based on the findings obtained in this study, the experimental grade stresses are generally much higher than the values given in MS 544: Part 3. In conclusion, the grade stresses of Malaysian tropical hardwoods stated in MS 544: Part 3 are discordant with their genuine value.