Physical and Mechanical Properties Performance between Untreated and Treated with CCA Treatment at Different Age Groups of Fast-Growing Acacia Hybrid of Sarawak

Abstract

An effort was carried out to fully utilise fast-growing Acacia hybrid usage in the timber engineering field; however, the research data are still lacking. This paper aims to evaluate the physical and mechanical properties performance between untreated (control) and treated with 10% copper chrome arsenic of Acacia hybrid collected from Daikin Plantation Sdn. Bhd. Bintulu, Sarawak at air-dry condition at different age groups using the small clear method. Mechanical properties test refers to shear parallel to grain (tangential and radial directions), cleavage (tangential and radial directions), and tension parallel to grain test. Meanwhile, the physical properties test refers to moisture content (MC) and density test. After treatment, mechanical properties increase with an average of 13.67%; meanwhile, moisture content decreased with an average of 0.58% or 0.09% MC, and density slightly increased with an average of 0.44% or 0.002 g/cm3. Results indicate that 10-year-old Acacia hybrid exhibits the highest strength values in shear parallel to the grain, tension parallel to the grain, and cleavage, followed by 13-year-old and 7-year-old. Treated samples in the tangential direction performed better with consistent mean results than that of the untreated samples, while radial direction gave a high average strength increment when treated.

The Mechanical Strength Properties, Treatability Retention and Hazard Classification of Treated Small-Clear Fast-Growing Acacia mangium Superbulk at Different Age Groups

“…All timber planks underwent the natural air-drying process at SFC (Figure 1c). The natural air-drying process was chosen for this study to minimise strength failures such as various splits and cracks [10,20]. The timber planks had to achieve the permissible air-dry moisture content (MC), which is ±19% before performing further laboratory procedures, and it takes approximately one year to achieve that moisture content condition.…”

“…Hence, the timber sticks were marked according to mechanical testing: static bending (MOR and MOE), compression parallel to the grain, and shear parallel to the grain. The most suitable method suggested in the literature for testing timber samples is using the defect-free or small-clear sample method [10,21,22]. The samples were prepared in accordance with BS 373 [23].…”

“…There were no detectable diseases while the Acacia mangium plantations were young. However, as the plantations grew, they were found to be prone to a number of diseases [10,11]. Ting and Teng [2] also mentioned that the Acacia mangium has a higher tendency to have defects.…”

“…This study used CCA preservative, as it is widely used in the timber industry in Malaysia [10]. The treatability assessment of the timber was driven by the ability of the CCA preservative to penetrate the timber, or, in other words, the maximum amount of the preservative solution absorbed by the timber.…”

Performance and Modification of Wood and Wood-Based Materials

“…Another study [8] aimed to expand the fast-growing Acacia hybrid usage in the timber engineering field by using copper chrome arsenic (CCA) treatment. It was found that the treated samples in the tangential direction performed better than the untreated samples, while the radial direction gave a high average strength increment when treated.…”