Your search resulted in 166 documents. Displaying 25 entries per page.
The effect of treatments in boron steaming medium on boron leaching and strength properties of wood
2008 - IRG/WP 08-40409
The combined effect of boric acid impregnation together with boron steaming and steaming heat treatments were evaluated in this study. Boric acid pre-treated wood samples and untreated ones subjected to steaming heat and direct steaming treatment in a close reactor at 13 bar pressure and 180 ºC for 30 minutes. Compression strength parallel to grain of wood samples, leaching test and pH measuremen...
E D Tomak, Ü C Yildiz, S Yildiz, E Pesman
Changes in hygroscopic, mechanical and surface properties of Scottish-grown Sitka Spruce (Picea sitchensis) wood subjected to dry heat treatment
2008 - IRG/WP 08-40415
Heat-treatment is a wood modification method which has been used to some extent in improving timber quality. However, the main limitation in the use of this technique despite its numerous advantages is the adverse effects on the various properties associated with the use of wood as an engineering material. Dry heat treatment of Scottish-grown Sitka spruce (Picea sitchensis) wood was carried out at...
L Awoyemi, M C Jarvis, A Hapca
Cantilever bending test of furfurylated poles
2008 - IRG/WP 08-40424
Ten, 8 m long poles of Scots pine (Pinus sylvestris) were treated with furfuryl alcohol to a WPG of approximately 40 %. A bending test was performed according to the principles in the draft European standard for wooden poles, prEN 14229 - Structural timber - Wood Poles for overhead lines. The bending strength and stiffness (MOE) for the poles tested were compared to an earlier study by the Swedish Wood Preservation Committee. In the latter study untreated, CCA-treated, ammoniacal Cu-PCP treated and creosoted poles were tested in bending. These types of poles were considered not to differ in strength and stiffness. The results of the furfurylated poles fit well with the results from the previous study. The bending strength and MOE values obtained are compared to the upper and lower 95-percentile values of the results from the previous study and all poles treated with furfuryl alcohol fit within this interval.Thus, this study indicates that a treatment with furfuryl alcohol does not result in a decrease of strength or stiffness. Further testing with a larger population of poles is necessary in order to get a statistically reliable result. In addition to further demonstration of the durability, the
treatment process must be optimised to ensure full sapwood penetration and measures have to be taken to avoid the serious cracking observed in this trial before furfurylation can be considered for treatment of Pinus sylvestris poles.
R Ziethén, J Jermer, A Clang
Material properties of acetylated beech plywood
2008 - IRG/WP 08-40425
The effect of acetylation process on dimensional stability and mechanical properties of plywood made by Oriental beech layers (Fagus orientalis Lipsky) were studied. The layers cut into sizes of 200×200×2 mm and acetylated in 120°C for 30 and 60 min.
Thickness swelling (TS%), water absorption (WA%) and anti-swelling¬ efficiency (ASE%) of specimens were measured. Mechanical properties (MOE, MO...
A Talaei
High Temperature Treated Wood
2008 - IRG/WP 08-40429
High temperature can modify internal structure and physic-chemical properties of wood by a controlled pyrolysis process. Such treatment, among other changes in properties, modifies the wood color in a way that resembles exotic species, increasing its market value. The main objective of this work is to determine the changes in wood properties caused by the effect of temperature and time, in order t...
C C Borges, A L Barbosa, R Faber de Campos, S T Targas
Termite resistance of some modified wood species
2009 - IRG/WP 09-40449
During the last few decades, researchers worldwide have investigated and developed new treatment techniques to improve intrinsic wood properties. Some of these techniques were introduced to the market recently and are gaining in importance.. Various wood properties of these new materials have been studied intensively. These include physical-mechanical properties (dimensional stability, moisture ...
H Militz, B C Peters, C J Fitzgerald
Wettability and bonding strength of wood thermally-treated with different combinations of soy oil and chemical additives
2009 - IRG/WP 09-40454
Thermal treatment is a method which has gained wider acceptability as an alternative to the chemical treatment in wood preservation. In order to maximize the benefits of this technique several options have been adopted including the use of soy oil in transferring the heat to the wood. Available information on thermal treatment in general and the oil method in particular show that there are still n...
L Awoyemi, P A Cooper, T Ung
Barefoot-heat-impact of oil-heat-treated wood: An important thermal property of decking boards
2009 - IRG/WP 09-40458
In this study the phenomenon of sensual heat impression was examined, when walking with bare feet on sun exposed wood based decking boards. A suitable method for measuring the heat flux from decking boards into an artificial foot was developed. The method and measuring device is described as well as results from measuring three different decking board materials: Oil-heat-treated spruce (OHT), untr...
A O Rapp, C R Welzbacher, C Brischke
Estimating the heat treatment intensity through various properties of thermally modified timber (TMT)
2009 - IRG/WP 09-40459
The suitability of different measures for prediction of the heat treatment intensity was investigated. Therefore, the resistance to impact milling (RIM), the lightness L*, the equilibrium moisture content (EMC), the anti swelling efficiency (ASE) and the total amount of soluble carbohydrates (TSC) of heat treated specimens were correlated with corresponding fungal resistance achieved by heat treat...
C R Welzbacher, C Brischke, A O Rapp
The effect of chemical changes on the wood-moisture relationships in thermally-modified wood
2009 - IRG/WP 09-40473
Small specimens of three wood species were thermally modified following twenty schedules in the 190-245°C temperature range for treatment times between 0.3 and 16 h. Five wood-moisture relations were subsequently determined, namely: anti-swelling efficiency (ASE), movement, hygroscopicity (adsorption and desorption), transversal swelling (radial and tangential directions), and equilibrium moistur...
M M González-Peña, M D C Hale
Influence of extractives on durability of Cupressus lusitanica heartwood
2010 - IRG/WP 10-10716
Identification of extractives present in Cupressus lusitanica heartwood has been conducted using GC-MS analyses. The chromatogram of toluene/ethanol extracts indicated the presence of high amounts of benzaldehyde and numerous of terpenic compounds such as cedrol, agathadiol, epimanool, bornyl acetate, -cedrene and -cedrene. Effect of extractives on cypress natural durability has be...
A Mohareb, P Sirmah, L Desharnais, S Dumarçay, M Pétrissans, P Gérardin
Measurements of rot fungal activity as a function of moisture content by isothermal calorimetry
2010 - IRG/WP 10-20428
Measurements of heat production rate have been made on wood samples with the brown rot fungus Postia placenta at different moisture contents. The results clearly indicate that the heat production rate (a measure of respiration rate and activity) is moisture dependent. When the moisture content is decreased, less heat is produced, and when the moisture content is increased, more heat is produced. I...
L Wadsö, A Pilgård, G Alfredsen
The Effects of Natural Weathering on the Properties of Heat Treated Alder Wood
2010 - IRG/WP 10-40484
Heat treatment is an effective method to improve the dimensional stability and biological durability of wood. The heat treatment technology and the heat treated wood products were recently introduced to Turkey. However, only a few studies have been reported on the effect of natural weathering on the properties of heat treated wood in both Turkey and the world. In this study, heat treated alder (Al...
S Yildiz, Ü C Yildiz, E D Tomak
Development of markers to predict decay durability of heat treated wood
2010 - IRG/WP 10-40496
Effect of heat treatment temperature on elemental composition of Scots pine sapwood (Pinus sylvestris) has been investigated in the range of temperatures between 220 and 250°C. Results revealed an important increase of carbon content, while oxygen content significantly decreases. Independently of the heat treatment temperature, elemental composition is strongly correlated with the mass losses due...
Ž Šušteršic, A Mohareb, M Chaouch, M Pétrissans, M Petric, P Gérardin
TMT–Interlab–Test to establish suitable quality control techniques - Structure and first results
2010 - IRG/WP 10-40503
As a result of growing quality demands from manufacturers and end-consumers of thermally modified timber (TMT) recent scientific research activities are increasingly focussed on modification mechanisms and by this on the development of suitable quality control methods. To deepen the knowledge in modification mechanisms and to obtain a larger variety of scientific data for TMT depending on the trea...
C R Welzbacher
An investigation on some physical properties of oil heat treated poplar wood
2010 - IRG/WP 10-40509
In this study some physical properties of small samples (20×20×20 cm) of poplar wood
(Populus nigra var.pyramidalis) after oil heat treatment with linseed oil was investigated. Two time levels (4.5 & 6 hours) and three temperature stages (180,200 & 220°C) were selected. The results of this study showed significant differences in effects of treatment temperature on physical properties of wood....
B Bazyar, D Parsapajouh, H Khademiesalam
Durability of heat treated Malaysian bamboo Gigantochloa scortechinii strips
2010 - IRG/WP 10-40514
Bamboo is one of the fastest growing plants and can be used for various products. In tropical countries such as Malaysia bamboo is abundantly available at reasonable prices, therefore it is used for numerous purposes. However, bamboo (as a lignocellulosic material) is susceptible to fungal and insect attack and it is difficult to protect by preservative treatment. Heat treatment is an option to im...
N Kamarudin, K Sugiyanto
Comparative Study of Heat Treatment of Beech Wood in Hot Water and Steam Medium
2010 - IRG/WP 10-40536
Heat treatment of wood is an effective method to improve the dimensional stability and durability against biodegradation. Heat treatments of beech wood in 2 different mediums (hot water and steam) in 180ºC were compared in physical, mechanical and anatomical properties. Mass loss in hydrothermally treated wood was higher than hygrothermally treated samples. Mechanical properties (MOR, MOE and CS)...
A Talaei, K Yaghoobi, A N Karimi
ISPM No. 15 and the Incidence of Wood Pests: Recent Findings, Policy Changes, and Current Knowledge Gaps
2011 - IRG/WP 11-30568
Largely as a result of international trade, hundreds of species of bark- and wood-infesting insects have become established in countries outside their native range. Many of these exotic insects have caused severe economic and environmental impact to urban and forest trees in the receiving countries. Most bark- and wood-infesting insects have been transported to new countries by means of the wood...
R A Haack, E G Brockerhoff
Thermally modified timber (TMT) for decking applications – determination of relevant surface properties
2011 - IRG/WP 11-40544
In recent years thermally modified timber (TMT) entered various market segments. It is used for facades, horticultural equipment, garden furniture, and also for kitchen and bathroom cabinets. However, flooring turned out to be the most important application for TMT, either as interior parquet or as exterior decking. Besides durability and dimensional stability, which had been the initial target pr...
L Meyer, C Brischke, C R Welzbacher
Effects of Heat-Treatment in Hot Water and Steam Mediums on Gas Permeability of Beech Wood
2011 - IRG/WP 11-40557
Heat-treatment, as a major method of wood modification, improving dimensional stability, and natural durability, has been studied greatly from different aspects. The effect of heat-treatment on gas permeability, as an important physical property of wood, in two different mediums of hot water and steam, as well as in two buffers of 7 and 8, is the main topic of the present study. Hydrothermal treat...
H Reza Taghiyari, A Talaei, A Karimi
Utilization of thermodesorption coupled to GC-MS to study kinetics of thermodegradation of different wood species
2011 - IRG/WP 11-40559
Thermdesorption coupled to Gas Chromatography coupled to Mass Spectroscopy (TD-GC-MS) has been investigated to identify volatile degradation products generated during wood heat treatment by mild pyrolysis. For this purpose, wood samples of different softwood and hardwood species have been heat treated under nitrogen for different temperatures comprised between 180 and 230°C during 15 min. in the ...
K Candelier, M Chaouch, S Dumarçay, A Pétrissans, M Pétrissans, P Gérardin
Effects of nano-silver on brittleness of heat-treated solid woods
2011 - IRG/WP 11-40572
The present study is aimed at the effect of heat-treatment of normal as well as nano-silver-impregnated Populus nigra, Populus deltoides, and Fagus orientalis on brittleness. Specimens were impregnated with 200 ppm water-based solution of nano-silver particles under 3 bars in a pressure vessel using empty-cell process. For heat treatment, both nano-silver-impregnated and normal specimens were kept...
H Reza Taghiyari, B Moradi Malek, A Karimi
The overview of ISPM 15 implementation in Croatian wood-working companies
2011 - IRG/WP 11-30576
Croatia is a small European county, but in the same time a great country according to it’s tradition in the forestry and wood working industry. However, around 48% of it’s territory is afforested. As the export is one of the main directions in the Croatian development conception, the production and distribution of wood package intended for the international trade, is one of the most important ...
R Despot, V Jambrekovic, M Hasan
Influence of heat treatment intensity on the structural integrity of 14 timber species
2012 - IRG/WP 12-40586
Thermally modified timber (TMT) is characterized by improved durability and dimensionally stability, but strength properties, especially the dynamic ones, are compromised at the same time. Because dynamic standard tests require high efforts and time, the high-energy multiple impact (HEMI) –test was developed for the fast and reliable characterisation of the structural integrity of TMT, showing a...
C R Welzbacher, C Brischke, G Maier