Mechanical Properties of Small Clear Wood Specimens of Pinus patula Planted in Malawi

Published Date

DOI: 10.4236/ojf.2014.41002

Author(s)    

Felix Dalitso Kamala, Hiroki Sakagami, Junji Matsumura

Affiliation(s)

Graduate School of Bioresource and Bioenvironmental Sciences, Kyushu University, Fukuoka, Japan.

Faculty of Agriculture, Kyushu University, Fukuoka, Japan

Faculty of Agriculture, Kyushu University, Fukuoka, Japan

ABSTRACT

Pinus patula is one of the major exotic species grown in Malawi mainly for saw-timber production. It is native to Mexico. Little has been reported about the mechanical properties of the wood. The objective of this study was to investigate the mechanical properties of Pinus patula in more detail, in order to provide a basis for utilizing this resource. The mechanical properties of small clear wood specimens of Pinus patula were evaluated using 40 cm logs from 1, 3, 5, 7 and 9 m above the ground. Small clear wood specimens were selected and subjected to a bending test in accordance with Japan Industrial Standards (JIS) air-dry conditions. The growth rate did not affect the mechanical properties measured. There were significant correlations at 1% level between air-dry density and Modulus Of Elasticity (MOE) (R = 0.85) and between air-dry density and Modulus Of Rupture (MOR) (R = 0.83). There was also a significant correlation between MOE and MOR at 1% level (R = 0.90). At about 12% moisture content, the tested five Pinus patula families have average MOR and MOE of 105.17 MPa and 10.93 GPa, respectively.

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