Sains Malaysiana 43(2)(2014): 211–218

Investigation of Linearity between Mechanical Properties of Wood Using Graphical Method

(Analisis Hubungan Linear Beberapa Sifat Mekanik Kayu Menggunakan Kaedah Grafik)

MOHD JAMIL ABDUL WAHAB*¹& MOHD ZAMIN JUMAAT²

¹Makmal Kejuruteraan Kayu, Institut Penyelidikan Perhutanan Malaysia

52109 Kepong, Selangor, Malaysia

²Jabatan Kejuruteraan Awam, Fakulti Kejuruteraan, Universiti Malaya

50603 Kuala Lumpur, Malaysia

Diserahkan: 25 April 2012/Diterima: 26 Mei 2013

ABSTRACT

Some basic requirements are set for small clear specimen data to incorporate Malaysian timbers into equivalent European timber strength classes. In general, the correlation between structural and small clear specimen test results must be established for every timber group regardless of origin. This paper introduces a sort-plot technique for analysing the correlation of some mechanical properties of timber in selecting appropriate parametric model. Bending test was conducted on mixed species hardwoods for the determination of strength and stiffness values of both structural and small size specimens. The results showed that the sort-plot diagrams demonstrate an obvious linearity pattern between timber properties despite having poor regression values. The technique verified that properties of timber in structural and small size specimens correlated linearly

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Keywords: Coefficient of determination; relationship; strength test

ABSTRAK

Beberapa syarat asas ditentukan ke atas data daripada spesimen bersaiz kecil untuk tujuan pengelasan kayu kayan Malaysia di dalam kumpulan kekuatan kayu Eropah. Secara umum, perhubungan antara hasil ujian spesimen bersaiz struktur dan kecil perlu ditentukan untuk setiap kumpulan kayu tanpa mengira negara sumber. Kertas ini memperkenalkan kaedah atur-plot untuk menganalisis perhubungan beberapa sifat mekanikal kayu dalam menentukan model parametrik yang bersesuaian. Ujian lenturan telah dijalankan ke atas beberapa spesies kayu keras untuk menentukan nilai kekuatan dan elastik spesimen kayu bersaiz struktur dan kecil. Keputusan ujian secara gambarajah atur-plot menunjukkan corak linear yang jelas antara sifat kayu walaupun mempunyai nilai regresi yang lemah. Kaedah tersebut mengesahkan bahawa sifat spesimen kayu bersaiz struktur dan kecil berkait secara linear.

Kata kunci: Hubungkait; pekali penentuan; ujian kekuatan

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*Pengarang untuk surat-menyurat; email: mohdjamil@frim.gov.my