Your search resulted in 130 documents. Displaying 25 entries per page.
A combined method for drying and preserving wood in a single step process
2000 - IRG/WP 00-40183
Based on a convective dryer, this process allows to dry and treat wood blocks with diffusible preservatives in the same time. A boric acid solution (heated to fix the wet temperature of the system) is pumped and introduced in the flow system through a venturi, where the air coming back from the drying cell also arrives. The role of the venturi is to create a dispersion of boric acid solution micro...
O Colin, C Dupuis, E Mougel, A Zoulalian, M-F Thévenon
Survey of North American practice in conditioning forest products before preservative treatment
1972 - IRG/WP 308
Seasoning requirements for the wide range of forest products which are treated with preservatives and fire retardants must be capable of dealing with a very complex set of conditions which are summarized under a number of variables including type and hazard of end use, the most effective distribution of preservative, a wide range of cross sectional dimensions, the possibility of seasoning by a ran...
J Rak, T S McKnight
Changes in transverse wood permeability during the drying of rimu and radiata pine
1990 - IRG/WP 3636
When softwoods are dried and subsequently impregnated with waterborne preservatives two problems frequently occur, preservative screening of multi-salt preservatives and difficult re-drying. To study the causes, the permeability of rimu and radiata pine wood has been measured along the three principal directions. The radial and tangential permeabilities of the green sapwood of the two species were...
R E Booker
Partial seasoning and preservative treatment systems for pine roundwood
1982 - IRG/WP 3187
Experimental trials at FRI, Rotorua showed that the steaming schedule normally used for steaming and venting is also suitable for steaming and vacuum seasoning. Applying vacuum of up to -84 kPa immediately after steaming did not increase the initial loss of wood moisture significantly in comparison to steam/venting. The main improvement to wood condition by using steam/vacuum appeared to be to dis...
A J Bergervoet
Survey of practical methods for conditioning of forest products before preservative treatment
1971 - IRG/WP 39
The seasoning of forest products is undertaken for a wide range of end uses and is becoming increasingly required for applications and building construction and secondary manufacturing industries. A wide range of applications of new technology and specifically required seasoning schedules is being actively developed for such requirements, but less attention has been given to the means by which woo...
J Rak, T S McKnight
Comparing microbial colonisation and Decay Rates of Wood from Sound and Aphid-Killed Kenyan-Grown Mexican Cypress (Cupressus lusitanica)
2006 - IRG/WP 06-10599
Samples of wood from 10, 15, and 30-year old trees attacked and killed by the cypress aphid (Cinara cupressi) and sound Kenyan-grown Cupressus lusitanica trees were investigated for variations in moisture content, density and susceptibility to microbial decay. MC varied with tree age, a normal trend, and between samples from aphid-killed and sound trees. In samples from 10, 15 and 20-year old so...
R Venkatasamy
A comparison of rates of decay and loss in stiffness of radiata pine and Douglas fir framing lumber
2008 - IRG/WP 08-20378
Stiffness loss with time was recorded for untreated radiata pine and Douglas fir framing size lumber and preservative treated radiata pine which dad been pre-inoculated with Oligoporus placenta, a brown rot decay fungus isolated from decaying untreated radiata pine framing. Between stiffness measurements, samples were contained in a plastic tank located outside at ambient temperature. Index of Con...
M Hedley, D Page, J van der Waals
Emission Rates of Active Substances from Preserved Wood in Use Class 3
2008 - IRG/WP 08-50256
The evaluation of an active substance or a biocidal product under the Biocidal Products Directive (BPD) requires that an environmental risk assessment is carried out. The risk assessment for wood preservatives includes scenarios for preserved wood (e.g. cladding on a house), in which the
predicted environmental concentration (PEC) in soil is calculated, using an emission rate for the active subs...
E F Baines
Vacuum drying of European oakwood: Color, chemistry and anti-oxidant potency of wood. Improving appearance in forest value added products
2008 - IRG/WP 08-40432
In hardwoods used for decorative and appearance purposes, wood colour is one of the most important factors of wood quality; in addition colour is related with durability and biological decay of wood. Wood discolouration during drying is mainly affected by heat, light, physiological reactions, combinations of reactions, biochemical and chemical reactions, and micro-organisms attack. In freshly fell...
S Sandoval, W Jomaa, F Marc, J-R Puiggali
Influence of Copper Preservative Type on Earlywood and Latewood Distribution of Copper in Treated Wood
2010 - IRG/WP 10-40507
Some of the new water based copper containing wood preservative systems use particulate “micronized” copper as the primary biocide instead of the more traditional soluble amine copper based systems. Studies were conducted to investigate how this difference in the type of copper system might impact both initial and post drying distribution of the preservatives in wood. Of specific interest wa...
A Zahora
Comparison of laboratory and semi-field tests for the estimation of leaching rates from treated wood
2010 - IRG/WP 10-50274
The authorization of wood preservative formulations in the European Union according to the Biocidal Products Directive (BPD) includes the assessment of environmental risks by the emission of active ingredients. This risk assessment includes scenarios for preserved wood (e.g. house scenario, noise barrier), in which the predicted environmental concentration (PEC) for soil and water is calculated, u...
N Morsing, M Klamer, B Seidel, J Wittenzellner, M Maier, J Habicht
Chapter 11 - Preservation of talla bamboo
2007 - IRG/WP 07-10635-11
Researches revealed that the talla bamboo (Bambusa tulda Roxb.))
in Bangladesh could be full-cell pressure treated with CCA in green
and dry conditions. The dry bamboo gives higher loading
absorptions than green one when impregnated at same treating
conditions. Also higher absorptions are obtained at nodes rather
than internodes. Adequate penetration and retention results for
ground and wate...
A K Lahiry
Chapter 12 - Treatment Groups of Bamboo
2007 - IRG/WP 07-10635-12
Study on distribution of CCA in three major bamboo species in
Bangladesh, full-cell pressure treated at green and dry conditions
revealed two treatment groups and some treating principles. Higher
adequate treatment for ground and water contact use is only
possible by treating problematic bamboo species pre-kiln dried up to
half of its FSP and non-problematic species pre-dried up to FSP
(20% ...
A K Lahiry
Chapter 14 - Accelerated fixation of CCA-treated bamboo
2007 - IRG/WP 07-10635-14
Chromated copper arsenate type C (CCA-C) fixation study on
impregnated (with adequate w/v 6% CCA solution) then boiled,
oven-dried, normal, air-dried and steamed bamboo slices of airdried
borakbamboo (Bambusa balcooa Roxb.) of Bangladesh,
revealed almost complete fixation in steamed (accelerated fixation)
and air-dried (3 weeks, slow fixation) bamboo slices compared to
moderate to low fixati...
A K Lahiry
Theoretic discussion on the way and driving forces of moisture migration in wood during vacuum drying
2011 - IRG/WP 10-40538
Most of parameters in conventional drying cannot explain a lot of phenomena appeared in vacuum condition, so it is necessary to further explore the moisture migration way and driving forces in wood under vacuum condition. For the water movement channel in wood is very narrow, the characteristic of heat and mass transfer in wood is similar to that in microscale. This article applies theory of liqui...
Zhengbin He, Xueli Yao, Liqiong Chen, Songlin Yi
Multilayer hot-press drying and chemical modifying of poplar wood with urea-formaldehyde prepolymer
2011 - IRG/WP 10-40539
The objective of this study was to determine the technology of chemical modifying and multilayer hot-press drying on poplar wood. The chemicals were impregnated into cell lumen space by pulse-dipping machine to improve the dimension stability and mechanical property of timber. The timbers were compressed and dried by the multilayer hot-press drying to increase the density of timber. Results indica...
Guofeng Wu, Yifei Jiang, Sheng Yao, Junwen
Comparison of rates of wood decay from four different field test protocols following 4-5 years exposure at a site in New Zealand
2011 - IRG/WP 11-30565
The rate of decay of Pinus radiata was evaluated using four different field test protocols at a site near New Plymouth, New Zealand. The average Scheffer index was 86 over the five year period of testing. The field tests were an in-ground stake test (AWPA Std E7-01) and three above ground tests – lap-joint (AWPA Std E16-98), decking (AWPC protocol) and ground proximity tests (AWPA Std E18-06) T...
P Lobb, K Day, A Siraa
Evaluation effect of kiln schedule on Warp, Twist, Bow and surface checks in Poplar Wood
2011 - IRG/WP 11-40565
In this research, to establish a kiln-drying schedule for poplar (Populus nigra) lumber with 75 mm thickness that cut down from North Khorasan province in Iran, with three schedules T5-D2 (Forest Product Laboratory), T5-D3 and T8-D5 were adapted for drying the lumbers down to the final moisture content of 8±2%. primary dry bulb temperature each three schedules was adjusted at 49,49 and 54°C and ...
M. Akhtari, M.Arefkhani
Characterizing long term leaching behaviour of copper from preservative treated wood in a practical exposure scenario
2011 - IRG/WP 11-50278
To investigate the prediction of the long term emission of copper from preservative treated wood in a Use Class Class 3 scenario, treated boards were exposed vertically above ground to natural weather conditions. The study included two products; an amine copper ACQ-type formulation, air-dried after treatment to a 22 kg/m3 retention, and the same formulation which was hot oil vacuum dried after tre...
T Mark Venås, M Klamer
The activity of a wood-decaying fungus during drying and rewetting cycles measured by isothermal calorimetry
2013 - IRG/WP 13-20526
Wood decaying fungi are an essential part of any ecosystems as they are the main decomposers of cellulose and lignin-containing materials. But as wood is a common building material the risk for decay fungi growth and subsequent degradation of our construction material is a concern. There are important physiological aspects of the growth and activity of decay fungi that are unknown today, and witho...
S Johansson, L Wadsö, A Pilgård, G Alfredsen
Comparison of moisture loss and its increment during the rehearsal process based on natural drying and water soaking application with or without sealing the trial discs of Common black poplar (Populus nigra L.)
2013 - IRG/WP 13-40639
This study was subjected to be set up to prove the pattern of moisture loss and moisture increment within the same wood samples prepared as the discs (30x23±3 cm diameter) with or without the bark intact during drying and in the duration of the water soaking application. In this concept, wood was exemplified by Common black poplar (Populus nigra L.) of the five 12 year old trees that are grown in...
I Usta
A screening of factors that might influence the result of laboratory decay tests
2014 - IRG/WP 14-20548
Laboratory fungal decay tests provide important tools for performance testing of wood materials. But they are also hampered with some uncertainties regarding reproducibility. In addition to variation between fungal species and strains the test conditions are also believed to have some influence. The aim of this study was to screen the effect of a selection of test parameters that might influence t...
E Larnøy, G Alfredsen, A Treu, S Kolstad
Performance of kiln-dried and air-dried anti-sapstain treated pallet timber under use scenarios against wood discolouring fungi
2015 - IRG/WP 30669
During their lifespan there is a high probability that wooden pallets and packaging material will be exposed to rainfall or rewetting conditions, increasing the risk of growth of discolouring fungi. Kiln-drying of wooden pallets and packaging material without anti-sapstain treatment does not give efficient protection against wood discolouring fungi during rewetting periods. However additional temp...
A Steitz, E Stoyanova, N Pfabigan, R Gründlinger
Three-Dimensional Digital Image Correlation of Strains in Profiled Wood Decking Exposed to Wetting & Drying
2017 - IRG/WP 17-20611
We use three dimensional digital image correlation to measure the strains that develop at the surface of profiled radiata pine (Pinus radiata D. Don) deck boards subjected to a wetting and drying cycle. We hypothesise that surface profiling will change the pattern of strain distribution at the surface of deck boards by concentrating stresses at the base of profile grooves. Five groups of three deck board samples were produced from five different pieces of machine stress-graded radiata pine wood. Two wavy profiles, ribble or ripple, were tested. Flat unprofiled boards acted a control. Each board was fixed to a rigid frame and subjected to a wetting and drying cycle. Full field surface strain data was collected using 3D digital image correlation. Strains varied across the surface of both flat and profiled boards. Profiling changed surface strain patterns; strain maxima and minima developed in the profile ridges and grooves during wetting, respectively, but this pattern of strains reversed during drying. Such a pronounced reversal of strains was not observed when flat boards were exposed to wetting and drying, although there was a shift towards negative strains when flat boards were dried. We conclude that profiling changes surface strain distribution in deck boards exposed to wetting and drying, and causes high strains to develop in the grooves of profiled boards. These findings help explain why checks in profiled deck boards are mainly confined to profile grooves where they are difficult to see, and the success of profiling at reducing the negative effects of checking on the appearance of wood decking.
J Mallet, S Kalyanasundaram, P D Evansa
Influence of Drying Condition of Wood on Rusting of Nail
2019 - IRG/WP 19-40887
Recently in Japan, the durability of metal joint in wooden structures become important. Revised Building Standard Law was enacted in 2000 and Act on the Promotion of Popularization of Long-life Quality Housing was enacted in 2008 in Japan. Since then, the durability of the metal joints in the wooden houses becomes important. But there are not any detailed regulation for the durability of the metal...
H Ishiyama, N Wada, T Nishimura, T Mori