Your search resulted in 182 documents. Displaying 25 entries per page.
The effect of pretreatments on the impregnation of air-dried sawn Belgian spruce
1988 - IRG/WP 3490
In general the impregnation of airdried spruce results in a variable treatment and limited penetration. This is the result of pit aspiration that occurs during drying of the spruce sapwood and heartwood. Spruce timber is becoming of greater importance in Belgium and hence research for better treatment of this vulnerable wood species is needed. Squared airdried timber of different dimensions were e...
J Van Acker, M Stevens
Durability of heat-treated wood
1999 - IRG/WP 99-40145
Heat-treated wood from the French process were laboratory tested against decay using agar block test and a modified soil block test. Water absorption, bending strength, lignin content and acid number were also determined to evaluate the effect of heat treatment. Heat treated samples exhibit a higher lignin content and a lower acid number compared to untreated control indicating the degradation of ...
D P Kamdem, A Pizzi, R Guyonnet, A Jermannaud
The effect of water storage on the cell-structure of Sitka spruce (Picea sitchensis) with reference to its permeability and preservation
1970 - IRG/WP III 3A
Commercial treatment trials with full sized transmission poles have shown that water storage considerably improves the permeability of Sitka and Norway spruce. These results were confirmed by laboratory measurements which showed that in the sapwood of ponded Sitka spruce there is a vast improvement in permeability in all three grain directions. Heartwood permeability does not seem to be affected t...
J A Dunleavy, A J McQuire
Supercritical fluid treatment: Effects on bending strength of white spruce heartwood
1993 - IRG/WP 93-20008
The effects of supercritical carbon dioxide on wood strength were evaluated using white spruce heartwood, a species known to be especially susceptible to collapse during exposure to higher pressures. The effects of pressures of 2000 or 3600 psig and temperatures of 40 or 80°C were evaluated using 30 or 60 minute exposure periods. No significant differences were noted in modulus of rupture or modu...
S M Smith, J J Morrell, E Sahle-Demessie, K L Levien
Effect of climate, species, preservative concentration and water repellent on leaching from CCA-treated lumber exposed above ground
2001 - IRG/WP 01-50178
Few studies have examined leaching of chromated copper arsenate (CCA) from treated wood in above ground exposures due to the assumption that leaching is less severe compared to wood in continuous contact with soil or water. However, a significant portion of CCA treated wood is used for above ground applications, exposing considerable volumes of the preservative to precipitation and potential leach...
J L Taylor, P A Cooper
Kerfing reduces checking in ACA-treated western white spruce poles
1988 - IRG/WP 3477
Western white spruce poles, pressure treated with pentachlorophenol and ammoniacal copper arsenate (ACA) were installed in the Westham Island test site. The pentachlorophenol treated poles were unkerfed, while both unkerfed and kerfed ACA poles were placed in test. The checking and kerf width and depth were recorded at the time of installation. After ten years of weathering the checking characteri...
J N R Ruddick
Valid scientific names of wood-decaying fungi in construction timber and their vernacular names in England, Germany, France, Sweden, Norway and Denmark
1992 - IRG/WP 92-1546
The valid scientific names of 100 species of wood decaying fungi in construction timber are listed, the citation of authors' names is standardized, and an index of the most commonly used synonyms is compiled. For each species vernacular names used in England, Germany, France, Sweden, Norway and Denmark are listed. The list of names is an attempt to update the current use of the most impor...
F Rune, A P Koch
Cell wall microdistribution of chloropicrin and methylisothiocyanate in treated spruce
1989 - IRG/WP 3548
Chloropicrin and methylisothiocyanate (MIT) residues were observed using SEM/EDXA and TEM/EDXA in treated spruce wafers that had been exposed to the vapors of the two fumigant preservatives. Chlorinated residues from chloropicrin were found throughout the wood cell wall, even in acetone extracted material. The residues were most heavily concentrated in extractive materials in the rays, but unlike ...
G F Daniel, B Goodell
Differences in pH, electrical resistance, cation composition and NIR spectra of red spruce wood during early stages of brown rot degradation
2002 - IRG/WP 02-10449
Red spruce sapwood was exposed to degradation by the brown rot fungi Coniophora puteana, Postia placenta, Gloeophyllum trabeum and Serpula lacrymans for 0, 1, 2 or 3 weeks using a modified soil block assay design. Average weight losses over time ranged from 0-8.9% during this time period. Detectable changes in pH, electrical resistance and cation compostion were observed in the wood as early as 1 ...
J Jellison, S Kelley, B Goodell, D Hui, A Ostrofsky
Färbeverfahren zur Unterscheidung von Holzzonen mit unterschiedlichem Absorptionsvermögen, insbesondere bei Fichtenholz (Picea abies Karst.). [Staining method for distinguishing zones of wood with different absorption behaviour, particularly in spruce (Picea abies Karst.)]
1980 - IRG/WP 3163
A simple regressive staining method for crosscut wood surfaces is described. Phloroglucinol-hydrochloric acid serves as stain; flowing water and a solution of sodium carbonate are used for development and fixation of a picture showing the differences of absorption. Hydrophobic zones and, contrary to this, zones with a high water content can also be shown. Comparing green spruce wood before and dur...
S Cymorek
Accelerated diffusion treatment of sawn Sitka spruce grown in the UK
1986 - IRG/WP 3395
The treatment of 'green' sapwood and heartwood of Sitka spruce by diffusion methods was investigated. Steam/dip treatment processes gave increased solution uptakes and depths of penetration of copper in comparison with a simple dip treatment. Further investigation is required to reduce diffusion gradients with copper based formulations and to improve the penetration of '...
R J Murphy, D J Dickinson
Sawn timber of fir (Abies alba Mill.) - Treatability and usability for the Hazard Classes 3 and 4
1999 - IRG/WP 99-40147
Within a national research project, tests on the treatability on sawn timber of fir (Abies alba Mill.) in oscillation pressure, vacuum pressure and double-vacuum processes have been worked out with 95 trunks taken from 3 different altitude levels (up to a height of 590 metres, 600 to 990 metres and over 1000 metres) and from 4 different regions of Switzerland. As the treatability of round wood can...
E Graf, T Bör
Improved preservative penetration of spruce after pre-treatment with selected fungi. II. Creosote treatment, analysis and strength testing
1998 - IRG/WP 98-40106
This paper describes the creosote treatment and analysis of logs pre-treated with selected fungal agents as a method of increasing the porosity of the wood prior to preservative treatment. The paper also reports the subsequent strength testing of the timber to evaluate the effects of the fungal pre-treatment on the structural integrity of the wood.
European spruce logs were pre-treated with eithe...
E J Tucker, A Bruce, H J Staines, B Rosner, K Messner
Improved preservative penetration of spruce after pre-treatment with selected fungi. I. Fungal pre-treatment of pole sections
1998 - IRG/WP 98-40117
European spruce logs were pre-treated with either Phanaerochete chrysosporium, Dichomitus squalens, Trichoderma viride and Trichoderma aureoviride for incubation periods of between 1-4 weeks prior to pressure treatment with creosote in a commercial treatment plant and analysed for strength and creosote uptake (see part II Tucker et al.). A method to pre-treat logs was optimised. The pole sections ...
B Rosner, K Messner, E J B Tucker, A Bruce
Influence of surface coating on the leachability of boric acid and bifluorides from spruce wood
1995 - IRG/WP 95-50050
In the Netherlands, window joinery made from non-durable timber species (spruce) are widely protected with preservative rods. These rods contain non-fixing wood preservatives (e.g. bifluorides or boric acid). This reseach was performed to show the possible influence of a coating system to hinder the leaching of the active ingredients. The results of the leaching tests show, that bifluorides and ev...
W J Homan, H Militz
Ammoniacal wood preservatives for use in non-pressure treatment of spruce and aspen poplar. Part 2
1984 - IRG/WP 3274
A series of thermal diffusion treatments were carried out on unseasoned white spruce (Picea glauca (Moench) Voss) lumber and air dry aspen poplar (Populus tremuloides Michx.) timbers using an ammoniacal copper arsenate wood preservative. Under the specific conditions described, certain charges of lumber met the present Canadian Standards Association Wood Preservation Committee's requireme...
C D Ralph, J K Shields
Comparison of the anti-fungal efficacy of Cobra with drill perforation on oscillating pressure treated spruce transmission poles -Laboratory test
1988 - IRG/WP 3469
A laboratory method for measuring the depth of penetration of the fungicidal concentrations effective against basidiomycetes (brown rot) was developed. The tests on CCB oscillating pressure treated spruce transmission poles have shown that the depth of salt penetration can be increased by about 10 mm by a drill perforation before the impregnation. An even better penetration is reached, however, if...
E Graf, B Zgraggen
The effect of heat treatment on the properties of spruce
1994 - IRG/WP 94-40032
The effect of high temperature treatment (above 150°C) on the wood quality is studied at the VTT. Improved dimensional stability, lower equilibrium moisture content and increased durability against biodeterioration is achieved, depending on the environmental factors. The biodeterioration resistance of spruce is improved due to changes in chemical composition and lower equilibrium moisture content...
H Viitanen, S Jämsä, L Paajanen, A J Nurmi, P Viitaniemi
Monitoring a Timber Bridge in Norway
2004 - IRG/WP 04-40282
We have instrumented three different timber bridges in Norway for the Norwegian Public Roads Administration. The goal was to learn more about the properties of timber bridges. We have instrumented Evenstad Bridge, Daleråsen Bridge and the last year Flisa Bridge. All bridges are have creosoted glulam trusses and creosoted stress laminated deck. Evenstad and Flisa have an asphalt deck on top, while...
F G Evans
Fungal decay of acrylate treated wood
2004 - IRG/WP 04-30357
Natural durability of wood species is variable. Chemical wood preservatives, such as biocides are necessary for extension of their service life. Many methods have been developed to increase the resistance of wood and wood products against wood-destroying organisms during the last years. The most frequently used methods are chemical and thermal modification of wood. In wood modification the basic c...
Z Tiralova, L Reinprecht
Laser incising of spruce lumber for improved preservative penetration
1991 - IRG/WP 3646
Red spruce heartwood specimens were incised using a range of laser beam power levels and pulse durations. The penetration of CCA through these holes into the wood was monitored after pressure treatment. In addition, green and dried spruce samples were incised using two patterns with incision densities of either 16.1 holes/in² or 21.3 holes/in². Following CCA pressure treatment the samples were t...
B Goodell, F A Kamke, Jing Liu
Specifying preservative-treated resistant timber: Conforming to European Standards
2001 - IRG/WP 01-20235
The most common construction timbers used in the UK are of low natural durability and, generally, resistant to preservative treatment. These include species of spruce, hemlock and fir. However, their characteristically limited and non-uniform uptake of preservatives may still confer sufficient protection to give satisfactory durability performance in terms of biological resistance. This paper desc...
E D Suttie, A F Bravery, T B Dearling
Influence of the decay of spruce chips by the selected fungi on their chemical structure and the pulp properties
2004 - IRG/WP 04-10510
The paper focuses on changes in the weight and in the molecular structure of spruce chips submitted to long-term storing as well as to medium- and long-term model rotting degradation caused by some chosen fungi identified at storing processes on the pile. For the model decay of chips under laboratory conditions during 3 or 6 weeks the white-rot fungi: Phanerochaete chrysosporium, Heterobasidion an...
R Solár, L Reinprecht, A Geffert, F Kacík
The association of bacteria with the increased permeability of water-stored spruce wood
1973 - IRG/WP 325
A microbiological investigation was undertaken to check our earlier work on patterns of bacterial counts and pH changes in water-stored wood. A survey of industrial activity was conducted upstream from the storage site with a view to explaining the existing bacterial flora. Further experiments were carried out with spruce bolts in enclosed tanks, using lake water with its natural bacterial flora a...
J A Dunleavy, J P Moroney, S E Rossell
Bending strength of heat-treated spruce and pine timber
2002 - IRG/WP 02-40242
Heat-treatment of spruce (Picea abies) and pine (Pinus sylvestris) beams (45 x 145 mm) gave a reduction in bending strength of approximately 50%. The bending stiffness (modulus of elasticity) only decreased by 3.5%. Tests were carried out according to EN 408. Another effect of the heat-treatment was increased variation in bending strength. The 5th percentile value of the bending strength, the so c...
C Bengtsson, J Jermer, F Brem