Moisture content of timber species in Hong Kong

Dowel-bearing strength is a significant parameter for designing wood connection. The strength of timber connection can be influenced by the bolt diameter, wood grain direction either parallel or perpendicular, thickness of wood, moisture content and other parameters. The dowel-bearing strength test was conducted with a 12 mm bolt diameter dowel, for three different types of timber species, which were mengkulang (Heritiera sp.), kempas (Koompassia malaccensis) and pine (Pinus sp.) glulam. The dowel was placed parallel to the timber grain direction with a glue line at the center of the half-hole test. The 5% diameter offset load (F5%) for dowel-bearing strength (Fy) was determined by using the ASTM D 5764-97a whereas the dowel-bearing strength (Fh) was determined based on BS EN 383: 2007. The results of the three different types of wood showed that the Malaysian timber kempas and mengkulang were 51.740% and 32.966%, respectively, which were higher than the European timber pine. The results of the dowel-bearing strengths (Fh), which were based on the BS EN 383: 2007 gave higher values compared to ASTM D 5764-97a.

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Bamboo as future bio-industrial material: Physical behaviour and bending strength of Malaysia’s Beting bamboo (Gigantochloa levis)

IOP Conference Series Earth and Environmental Science ◽

10.1088/1755-1315/951/1/012001 ◽

2022 ◽

Vol 951 (1) ◽

pp. 012001

Author(s):

S Osman ◽

M Ahmad ◽

M N Zakaria ◽

A M Zakaria ◽

Z Ibrahim ◽

...

Keyword(s):

Mechanical Properties ◽

Specific Gravity ◽

Moisture Content ◽

Physical Properties ◽

Dimensional Stability ◽

Fiber Orientation ◽

Bending Strength ◽

Physical And Mechanical Properties ◽

Timber Species ◽

Industrial Material

Abstract In this paper, bending strength and physical properties (specific gravity, dimensional stability and equilibrium moisture content) of a Malaysian bamboo locally known as Beting bamboo (Gigantochloa levis) are addressed. Characterizations of physical and bending strength of G. levis in terms of the variability of location along culm height (top, middle, bottom), culm section (nodes and internodes), fiber orientation (longitudinal, tangential and radial) and culm layer (outer and inner) were conducted. Comparison of these properties is also made to some bamboo and commercial timber species. It was found that G. levis has favorable physical and mechanical properties although the specific gravity of G. levis has tendency to be on the higher side. The characteristics studied were found to have some variability at different locations, sections, and directions. There was variability in terms of bending strength along with the culm height of bamboo. It is indicated from this study that the bending strength and physical properties of G. levis were found to be satisfactory.

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Influence of timber moisture content on wave time-of-flight and longitudinal natural frequency in coniferous species for different instruments

Holzforschung ◽

10.1515/hf-2017-0113 ◽

2018 ◽

Vol 72 (5) ◽

pp. 405-411 ◽

Cited By ~ 11

Author(s):

Daniel F. Llana ◽

Guillermo Íñiguez-González ◽

Roberto D. Martínez ◽

Francisco Arriaga

Keyword(s):

Moisture Content ◽

Wood Species ◽

Radiata Pine ◽

Ultrasound Measurement ◽

Timber Species ◽

Longitudinal Vibrations ◽

Saturation Point ◽

Coniferous Species ◽

Adjustment Factors ◽

Non Destructive

AbstractNon-destructive techniques (NDTs) are well suited for rapid estimation of timber properties, but NDT results are affected by several factors, the most important of which is the moisture content (MC) of wood. Much of the research in this context was limited to ultrasound measurement of a few wood species, mainly to Norway spruce. The present paper investigates the MC influence on the NDT results obtained by instruments based on ultrasound (two devices), impact stress waves (one device) and longitudinal vibrations (two devices). A hundred large cross-section specimens of four timber species were tested, namely: radiata pine, Scots pine, Salzmann pine and maritime pine. The influence of MC on velocity was found to be stronger below the fiber saturation point (FSP) than above FSP. MC adjustment factors below FSP are proposed for these wood species.

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The Use of SEM/EDX Analysis to Investigate the Pore Effect on the Mechanical Properties of some Selected Tropical Hardwoods

International Journal of Engineering Research in Africa ◽

10.4028/www.scientific.net/jera.56.64 ◽

2021 ◽

Vol 56 ◽

pp. 64-76

Author(s):

Joseph Olawale Akinyele ◽

Abidemi Bashiru Folorunsho

Keyword(s):

Mechanical Properties ◽

Moisture Content ◽

Beech Wood ◽

Physical And Mechanical Properties ◽

Mechanical Tests ◽

Timber Species ◽

Edx Analysis ◽

Elemental Impurities ◽

Hardwood Species ◽

Three Samples

Previous studies have investigated the effect of moisture content on the physical and mechanical properties of timber species. This study investigated the effect of the tube-like grain pores in the wood and the presence of elemental impurities on the failure mechanism of four tropical hardwoods. The four hardwood species are Mahogany, Albizia, Beech and Birch. The moisture content of each wood specie was determined at normal temperature, mechanical tests were conducted to determine the strength of each wood samples, while the Scanning Electron Microscopy/ Energy Dispersion X-ray (SEM/EDX ) analysis was carried out to determine the high-resolution images and elemental peaks of the wood specie. The work concluded that beech wood failed earlier when compared to the other three samples due to high moisture content that is above the fibre saturation point. The SEM/EDX test revealed that the early failure was also as a result of the presence of large pores and elemental impurities in the sample of Beech wood.

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Determination of Swelling and Dimensional Stability of Some Nigerian Timber Species

Annual Research & Review in Biology ◽

10.9734/arrb/2020/v35i130177 ◽

2020 ◽

pp. 24-29

Author(s):

G. C. Ajuziogu ◽

A. N. Amujiri ◽

E. U. Njoku ◽

C. B. Ozokolie ◽

E. O. Ojua

Keyword(s):

Moisture Content ◽

Dimensional Change ◽

Timber Species ◽

Strong Positive Correlation ◽

Content Change ◽

Radial Dimension ◽

Dimension Stability ◽

Swelling Coefficient ◽

Timber Market ◽

Daniellia Oliveri

Aim: The absorption of moisture and dimensional distortion are the major shortcomings of wood utilization as building and furniture materials. This study was aimed at determining the moisture content, swelling ability and dimension stability of five selected timber species. Methods: The samples were collected with the help of the Forest Ranger from the Forestry Department of Enugu State, Nigeria, attached to the Nsukka timber market. The wood samples were evaluated for moisture content change, shrinkage or swelling (%) coefficient, amount of swelling and dimensional change. Results: The change in moisture content across the five species was in the order of Gmelina aborea < Milicia excels < Daniellia oliveri < Alstonia bonnie < Antiaris toxicaria. At 12hrs, Gmelina aborea recorded significantly (P < 0.05) the highest dimension change (46 ± 0.70%) in the radial dimension (direction) as compared to the other species except for Antiaris toxicaria. The swelling coefficient and the amount of swelling were observed to have a strong positive correlation with the dimensional change in the sampled wood. Conclusion: The lower swelling coefficient and the amount of swelling observed in Milicia excels among the five timber species, make it a more suitable species for industrial use.

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