TY  - EJOU
AU  - Baharin, Adnie 
AU  - Rosli, Muhammad Amirul Akmal 
AU  - Bhkari, Norshariza Mohamad 
AU  - Chen, Lum Wei 
AU  - Azmi, Anis 
AU  - Nordin, Muhammad Shaiful 
AU  - Ahmad, Zakiah 

TI  - Verification of Depth Adjustment Factor in Eurocode 5 for Tropical Hardwood Timbers
T2  - Journal of Renewable Materials

PY  - 2023
VL  - 11
IS  - 9
SN  - 2164-6341

AB  - The depth adjustment factor for bending strength stated in Eurocode 5 (EC5) is only applicable to timbers having
a characteristic density below 700 kg/m<sup>3</sup>
. However, most Malaysian timbers are hardwood, some with a characteristic density reaching above 700 kg/m<sup>3</sup>
. Therefore, the objective of this study was to examine whether the depth
adjustment factor stipulated in EC5 is valid for Malaysian hardwood timbers. Six timber species were selected for
this study, namely Kapur (<i>Dryobalanops</i> C.F.Gaertn.), Kempas (<i>Koompassia Maingay</i> ex Benth.), Keruing (<i>Dipterocarpus</i> C.F.Gaertn.), Light red meranti (<i>Shorea</i> Roxb. ex C.F.Gaertn.), Geronggang (<i>Cratoxylum</i> Blume) and
Balau (<i>Shorea</i> Roxb. ex C.F.Gaertn.). The determination of bending strength and characteristic density was conducted according to BS EN 408: 2010 and BS EN 384: 2016, respectively. A graph for mean bending strength vs.
(150/h) was plotted for each timber species. The power function was selected to analyze the relationship between
the two variables. The power of the regression equations varied depending on the characteristic density of the
timber species. For species with a characteristic density below 700 kg/m<sup>3</sup>
, such as Kapur, Keruing, and Light
red meranti, the power was between 0.16 to 0.17. In contrast, for species having a characteristic density above
700 kg/m<sup>3</sup>
, namely Kempas and Balau, the power was higher at 0.23 and 0.24, respectively. Geronggang was
an exception to this pattern. These values are close to the depth adjustment factor given in EC5, which is 0.2.
Based on the results, it can be suggested that the adjustment factor of 0.2 is also applicable to Malaysian hardwood
timbers with a characteristic density above 700 kg/m<sup>3</sup>
KW  - Depth adjustment factor; Malaysian hardwood timber; bending strength; Eurocode 5

DO  - 10.32604/jrm.2023.028675