Your search resulted in 328 documents. Displaying 25 entries per page.
Heat treated timber in Finland
2000 - IRG/WP 00-40158
Heat treatment permanently changes the physical and chemical properties of wood by means of high temperatures (150 - 240°C). Heat treatment darkens the colour of the wood. Heat treatment improves the equilibrium moisture content of the wood and the shrinkage and swelling of the wood is reduced. Very high temperatures improve the resistance to rot and also reduce the susceptibility to fungal decay...
T Syrjänen, E Kangas
Decay resistance of Scots pine (Pinus sylvestris) heartwood against brown rot
2002 - IRG/WP 02-10433
Natural decay resistance of wood is mainly restricted in the heartwood and based on wood microstructure and chemical composition. The genetic variation in the durability of Scots pine (Pinus sylvestris L.) wood against decay and the relationship between resistance and chemical composition was studied. The laboratory tests of 6 and 8 weeks were carried out with a brown rot fungus Coniophora puteana...
H Viitanen, A M Harju, P Kainulainen, M Venäläinen
Effect of wood moisture on ability of Sphaeropsis sapinea to colonise Pinus radiata
1999 - IRG/WP 99-10311
The factors influencing colonisation of unseasoned radiata pine logs by sapstaining fungi which can result in detrimental wood discolouration, are being explored. The objective of the current study was to determine the effect of wood moisture content on fungal growth and wood colouration (melanisation).
Five replicate trials were set up using increment cores (10mm diameter) which were taken from ...
B Kreber, D R Eden, R N Wakeling, C M Chittenden, J G Van der Waals, B Carpenter
Testing wood in ground contact: An artificial soil
1977 - IRG/WP 280
This document is an interim report on the development of the artificial soil medium. It includes some information on the relationship between soil, wood and water which is of relevance in testing....
E F Baines, D J Dickinson, J F Levy
Methods of assessing decay in poles in service with the Pilodyn wood tester
1978 - IRG/WP 2107 A
H Friis-Hansen
Field trials on preserved timber out of ground contact
1978 - IRG/WP 3154
This report describes two different field trials studying the performance of preservative treatments on timber exposed to the weather, but above the ground. Results are presented on the protection afforded against decay, and on the efficiency of water-repellent preservative treatments in controlling the uptake of moisture by the timber. Proposals for a standard field test system are briefly discus...
D F Purslow, N A Williams
Co-operative research at the Naval Research Laboratory on wood extractives and related compounds as antiborer agents
1977 - IRG/WP 429
J D Bultman, K K Parrish
The secondary treatment of creosoted electricity poles with fused boron rods
1988 - IRG/WP 3485
After preliminary trials selected poles were treated at the groundline with fused boron rods. Early samplings showed that movement was slow in the dry heartwood but after six years the distributions obtained indicate that the system has merit for the treatment of the heartwood of poles in service....
D J Dickinson, P I Morris, B Calver
Treating Eucalyptus tereticornis wood with boron: Optimizing treatment conditions
2005 - IRG/WP 05-40309
Even though Eucalyptus tereticornis wood is suitable for small timber purposes, being non-durable, it needs to be treated with preservative chemicals. As it is a heavy, hard and difficult to treat species, the possibility of using diffusible boron compounds was investigated. The present study explored the effect of impregnation conditions such as treatment schedule, concentration of treatment solu...
T K Dhamodaran, R Gnanaharan
Effect of permeability and extractives on the decay rate of southern pine sapwood in above grund exposure
2005 - IRG/WP 05-20310
The effects of wood permeability and hydrophilic and hydrophobic extractives on the decay rate of southern pine sapwood in above ground exposure were investigated. Permeability was determined by water sorption measurements, and the effect of extractives was studied by pre-extracting the test samples prior to outdoor exposure using water to extract hydrophilic extractives or sequential methanol/cy...
D D Nicholas, T Schultz, L Sites, D Buckner
The use of plastic meshes in soft rot monoculture testing
1990 - IRG/WP 2353
Plastic meshes were introduced between the wood blocks and agar medium in a miniaturised soft rot monoculture test in order to minimise transfer of the preservative from the wood and mineral salts from the agar. Although several different sizes and types of mesh were used and the blocks were wetted up to an appropriate moisture content for soft rot attack the amount of decay was substantially redu...
S M Gray
Artificial drying of impregnated wood
1987 - IRG/WP 3448
Sawn timber (Pinus Sylvestris) of dimension 50x150 mm was impregnated with CCA by a full-cell process. The timber was then dried in a conventional kiln or a special vacuum kiln where the timber was dried by circulating superheated steam. Drying time was 16 days and 2 days respectively. The aim of the investigation was to compare the physical appearence of the wood after drying by the two methods w...
M-L Edlund
Decay, decayed wood and the Shigometer
1980 - IRG/WP 281
A L Shigo
Influence of variable lignin content on brown rot decay of wood
1987 - IRG/WP 1320
Compilation of published data and new experiments with brown-rotting fungi on different timber species suggest that their decay activity, in contrast to soft rot and white rot fungi, is not greatly influenced by the type or amount of lignin present....
T Nilsson, G F Daniel
Investigation of microwave as a means of eradicating dry rot attack in buildings
1992 - IRG/WP 92-1545
A microwave-apparatus developed for treatment of building-structures infested by dry rot was tested in the laboratory. The test-conditions simulated treatment of either infested timber or infested brickwork. Sawdust samples, both wet and dry, infested by viable mycelium of Serpula lacrymans were packed in glass-tubes. The tubes were then placed in the middle of either 20 cm thick wooden beams or 3...
C Kjerulf-Jensen, A P Koch
The chemical analysis and biological evaluation of wood extractives as potential timber preservatives
1995 - IRG/WP 95-30090
Work involved the biological performance of water and organic solvent soluble extractives of four naturally durable wood species, namely; Matumi, Tamboti, Sneezewood and the Turpentine tree. These timber species are known to be naturally durable against termites and fungi (±25 to 35 years). The extractives were evaluated against termites and fungi using impregnated pine pencil stakes in field tes...
P Turner, D Conradie
Moisture condition in treated wood exposed outdoors. A progress report after 5 years
1992 - IRG/WP 92-3720
Wood treated with water-borne preservatives, mainly CCA (copper, chromium and arsenic) and CCB (copper, chromium and boron) is often said to absorb more water than untreated wood. In laboratory tests this statement has not been confirmed (Johansson 1977). In 1986 a project was started to compare water absorption during outdoor exposure between wood stakes of pine, Pinus sylvestris L, and spruce, P...
M-L Edlund
Development on Damage Functions of Wood Decay for Building Envelope Design
2005 - IRG/WP 05-10556
For the hygrothermal analyses of building envelope systems for insulation design, we tried a natural decay test of wetted wood specimens without any inoculation of fungi. Three principal experimental types: under steady-state conditions (Experiment A), at a cyclic water dripping under Non-steady conditions (Experiment B) and at a cyclic water dipping under-steady conditions (Experiment C), were ca...
H Suzuki, Y Kitadani, K Suzuki, A Iwamae, H Nagai
Susceptibility of harvested softwoods to infection by sap-staining fungi
2002 - IRG/WP 02-10435
In the UK a field study programme was carried out to compare the susceptibility of softwood timber from five different commercially important tree species to infection by sap-stain fungi. Logs cut from freshly felled Scots pine (Pinus sylvestris), Lodgepole pine (P. contorta var.
latifolia), Sitka spruce (Picea sitchensis), Norway spruce (P. abies) and Japanese larch (Larix leptolepis) were expo...
E J Young, R A Eaton, J F Webber
The possible significance of the lignin content and lignin type on the performance of CCA-treated timber in ground contact
1988 - IRG/WP 1357
The lignin in wood samples of Alstonia scholaris, Octomeles sumatrana and a Simaruba species have been analysed. These timbers are characterised by a high lignin content and low syringyl:guaiacyl ratios. Decay tests with two soft rot fungi showed that the timbers were less susceptible than timbers with a low lignin content and higher syringyl:guaiacyl ratios. Numerous data for field performance of...
T Nilsson, J R Obst, G F Daniel
Moisture condition in treated wood exposed outdoors. A progress report
1989 - IRG/WP 3533
Wood treated with water-borne preservatives, mainly CCA (copper/chromium/arsenic), CCB (copper/chrome/boron) or CC (copper/chrome) is often said among users in Sweden to absorb more water than untreated wood. In laboratory tests this statement has not been confirmed but no field tests have been carried out in Sweden to study this phenomenon. In 1986 a project was started to compare water absorptio...
M-L Edlund, C E Sundman
Relationship between bond strength and surface characteristics of CCA-treated Douglas-fir
1993 - IRG/WP 93-30008
Chromated-copper-arsenate (CCA) treated Douglas-fir was laminated using a commercial phenol-resorcinol resin. CCA treatment enhanced the water repelleney of wood espeeially in the presence of extractives. However, the shear strength of CCA treated wood was 12% lower in dry condition and 38% lower in wet condition after six cycles of vacuum-pressure test than that of untreated wood. Slight removal ...
K Yamamoto, J N R Ruddick
Co-operative research project on L-joint testing. Progress report to March 1984
1984 - IRG/WP 2211
Each participant was intended to expose L-joints in the main trial on 1 April 1983 and the first sampling, after 8 months exposure, was to be undertaken on 1 December 1983. Some participants have had to vary this schedule. Results are presented from CTFT (France) and PRL (United Kingdom). These show a greater effectiveness by the double vacuum treatments compared with the 1 minute dip treatments. ...
J K Carey, A F Bravery
Comparative study on physical properties of four fast growing timber species of Bangladesh
2006 - IRG/WP 06-10570
Ghoraneem (Melia azedarach), Rain tree (Albizia saman), Sissoo (Dalbergia sissoo Roxb.) and Akashmoni (Acacia auriculiformis) plantations are started as a fast growing timber specie from a few years back in Bangladesh. Initian objectives were to get fuel wood only from those trees, but a very positive response was found for Ghoraneem, Rain Tree, Sissoo and Akashmoni timber in the users market by c...
M M Islam, B K Dey, M O Hannan, G N M Ilias
UV-microspectrophotometry of lignin and accessory compounds in wood cell walls of conifers
1999 - IRG/WP 99-20171
The distribution of lignin in the cell wall of conifer tracheids was determined by UV-VIS microspectro-photometer. Wood sections of one micron thickness were measured between the wavelength 240 and 700 nm. Spectral analyses revealed that the conifer lignin associated with the tracheid secondary wall and middle lamella is composed of guiacylpropane units which exhibit a characteristic UV absorption...
G Kleist, G Koch, J Bauch