Your search resulted in 258 documents. Displaying 25 entries per page.
An evaluation on durability of untreated mining timber support
1997 - IRG/WP 97-20121
Wedge blocks in dimension of 5 x 7 to 8 x 155 cm3 were cut from indigeneous scots pine pitprops. Each of wedge block pairs were numbered and half of them were placed as the test blocks between the steel arches and the strata in a hard coal pit. Controls in laboratory and test wedge blocks in the mine were then sawn into 20 by 20 by 300 mm standard test sticks. Impact bending, static bending and MO...
A Bobat
Vapour boron treatment of wood based panels: Mechanism for effect upon impact resistance
1994 - IRG/WP 94-40036
Samples of medium density fibreboard, chipboard and oriented strandboard (OSB) were treated to two retentions of boric acid by a vapour phase treatment. The results of a range of mechanical tests were reported by Hashim et al. (1992, 1993) in which a small reduction in impact resistance was observed. Several investigations were carried out to study how and where this loss in impact resistance occu...
R Hashim, R J Murphy, D J Dickinson, J Dinwoodie
The use of a physical field model to study the effects of remedially treated timber on the growth of perennial ryegrass (Lolium perenne) and rye (Secale cereale), and the accumulation of toxic preservative constituents in Lolium perenne
1995 - IRG/WP 95-50040-02
Low cost laboratory model systems can be used to give relatively rapid indications of the environmental effects of preservative treated timber in soil contact. This paper details the effects of remedially treated timber on the growth of crops of Lolium perenne and Secale cereale seeded on soilbeds of different texture in close proximity to remedially treated creosoted pole sections. Lolium perenne...
D C R Sinclair, G M Smith, A Bruce, H J Staines
A simple non-destructive means of testing poles in situ
1982 - IRG/WP 2167
Anonymous
Fully impregnated poles for a minimum environmental impact: Eucalyptus poles
2005 - IRG/WP 05-50224-24
The classical processes for preservation of wooden poles (vacuum-pressure and Boucherie processes) allow the impregnation of the sapwood only.
The new radial-axial injection process has been applied to Eucalyptus poles, and has led to impregnation of both sapwood and heartwood.
Further more; preserving product is injected both through the groundline area and through the bott end. This allows the...
L Nitunga
Bending creep test of plywoods under long term exposure to fungal attack
1981 - IRG/WP 2163
Bending creep test and decay test were coupled in order to evaluate the durability of structural plywoods and preservative efficacy. Experimental blocks, 5.0 x 1.2 cm² section x 35.0 cm length, were impregnated with distilled water and inoculated with mycelial fragments of test fungus. Polyethylene bags stretched with metal frame were used as decay chambers. The chambers containing inoculated blo...
M Takahashi
Mechanical resistance of Pinus radiata CCA treated and face jointed with PVA adhesive
1999 - IRG/WP 99-40140
Due to the increased use of Pinus radiata timber composites (laminated structural members, panels, etc), its low natural durability and the toxicity of phenol-formaldehyde type adhesives, a PVA (polyvinyl acetate) adhesive was evaluated in machined and rough CCA treated and untreated face joint samples under DIN 68602 (EN 204-205) standard for groups of requirement 3 and 4. The results showed that...
M C Rose, L Reyes, P León
Rapid analytical methods for wood waste - An overview
1998 - IRG/WP 98-50104
The proper handling of wood after service is a today's problem. Untreated wood could be reused or may be used as fuel. For treated wood special care is demanded to avoid environmental impacts. Thus, analytical methods are requested to detect rapidly whether and to what extend wood is contaminated, covering a wide spectrum of organic and inorganic agents used during the last 50 years. Trad...
A Peylo, R-D Peek
Bending Properties of FRT OSB
2012 - IRG/WP 12-40600
Fire retardant treated (FRT) oriented strandboard (OSB) and plywood of different widths were tested in static bending to determine width effects. Results were consistent with previous width effect studies and showed that increasing specimen width results in a decrease in sample MOR properties among all the sample groups tested in this study. Increasing sample width for OSB samples leads to more ...
J M Hill, H M Barnes, S Q Shi
Bending properties of TCMTB-treated Southern pine sapwood using supercritical carbon dioxide impregnation process
1997 - IRG/WP 97-40080
The effects of elevated pressure and treatment with thiocyanomethylthiobenzothiazole (TCMTB) on the bending properties of Southern pine sapwood were evaluated at pressures ranging from 1,800 to 3,600 psi. All bending properties were affected to some extent by supercritical fluid treatment. Modulus of elasticity and work to maximum load were not significantly affected by pressure levels. Modulus of...
Gyu-Hyeok Kim, S Kumar, E S Demessie, K L Levien, J J Morrell
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
Accelerated laboratory soil contact decay test using soil amended with composted wood
2004 - IRG/WP 04-20284
The effect of amending soil with wood compost on the decay rate of wood wafers in contact with the unsterile soil, as measured by radial compression strength loss, was explored. It was found that the addition of composted wood to the soil significantly increased the wood decay rate. The reason for this acceleration in wood decay is not entirely clear, but appears to be at least partially associate...
D D Nicholas, H Borazjani, T Schultz
Treatment of wood with formaldehyde. Acid catalysis of the reaction between formaldehyde and wood
1980 - IRG/WP 3146
Formaldehyde reacts with the free OH-groups in wood forming cross-linking bonds. The reaction can be brought about without any catalyst but in that case the activation energy is very high and high temperatures and long reaction times are needed. Normally, the reaction is catalysed by different acids. Acid catalysts, however, tend to degrade the cellulose and the wood matrix causing reduction in th...
T Vihavainen, K Piispanen, P Mansikkamäki
Assessment of dehydrogenase activity, fluoride content and total chromium content of soil profiles exposed to preservative treated wood within a model system
1993 - IRG/WP 93-10015
The development and prospective use of a closed model system to facilitate study of a number of indicators of environmental impact of wood preservatives laboratory conditions has been described (IRG/WP/2395-92). Chemical analysis of leachate samples collected from drained soil profiles containing creosoted pole sections remedially treated with a chromated fluoride preservative indicated small incr...
G M Smith, D C R Sinclair, A Bruce, H J Staines
Microscopical analysis of formaldehyde-acid modified wood
1981 - IRG/WP 3182
Cross-linking of wood with gaseous formaldehyde improves its hygroscopic and dimensional behaviour, and its resistance against micro-organisms. However, formaldehyde cross-linking reactions take place only in the presence of an acid catalyst, which results in losses in mechanical By optimization of a formaldehyde-sulfur dioxide vapour phase process the reaction conditions were established to limit...
M Stevens, N Parameswaran
Some experiences with attack of microorganisms on wooden constructions supporting foundations of houses and bridges
1997 - IRG/WP 97-10232
Reconstructions of bridges and public buildings or damage of houses during the construction of subway lines in Berlin have led to a number of inspections of wooden foundations, mostly pine or spruce piles, representing service lives of between ca. 70 and 140 years. In all cases bacterial attack was found both in wood submerged in ground water and in surface water. The extent of deterioration diffe...
M Grinda
Life-cycle assessement of treated wood: A view from the roa
1996 - IRG/WP 96-50078
Life Cycle Assessement (LCA) is being used increasingly as a tool to structure information on the environmental characteristics of material and processes. This paper is based on the experience gained from our LCA studies on treated wood products over the last 4 years. The comprehensive and logical examination af the information available on treated timber provided by LCA has allowed identification...
W Hillier, R J Murphy, D J Dickinson, J N B Bell
Initial results and observations of a model system to assess the efficacy and environmetal impact of preservative treated wood
1993 - IRG/WP 93-50001-02
The development of a closed model system for the laboratory assessment of the efficacy and environmental impact of a chromated fluoride remedial treatment for creosoted distribution poles has been described (IRG/WP/2395-92). The model consists of a precipitation apparatus above a treated pole section positioned in a soil profile from which leachate was collected via a series of simulated field dra...
D C R Sinclair, G M Smith, A Bruce, H J Staines
Field stake test assessment with the Pilodyn
1980 - IRG/WP 2136
The Pilodyn, which was originally developed to estimate the degree of soft rot in wooden poles, was thought to have potential for giving a quantitative measure of the extent or depth of decay in field test stakes. In the present work a 2-joule Pilodyn with 2.0-mm diameter pin was used in an attempt to limit depth of pin penetration (to 10-15 mm) without reducing scale sensitivity. The results show...
M E Hedley, R W Naish
Acetylated solid wood. Laboratory durability test (part 2) and field trials
1995 - IRG/WP 95-40048
Degradation of acetylated beech, pine and poplar by soft rot fungi was related to strength loss in a laboratory test. No strength loss was noticed for poplar acetylated to a weight percent gain (WPG) of more than 11.2% and beech with a WPG of 12.8%. Several field trials were set up to determine the durability of acetylated products in practice. They included a field test to determine the durabilit...
E P J Beckers, H Militz, M Stevens
Délavabilité de bois ronds traités avec un sel CCA dans des conditions réelles de stockage. Incidence pratique de la fixation accélérée par étuvage. Impact effectif sur l'environnement
1993 - IRG/WP 93-50001-23
Un essai de terrain a été organisé pour mesurer concrètement, dans des conditions aussi proches que possibles des conditions réelles de terrain, les pertes effectives en produit de traitement lorsque le bois traité est soumis à des intempéries. L'essai a été conduit sur des bois ronds (poteaux), traités en autoclave par procédé Bethell avec un sel CCA de type C, avec comme fi...
M Rayzal, F Larroze
The degradation of wood surfaces by water
1984 - IRG/WP 3289
Thin radial/longitudinal sections (~100 µ) of Scots Pine (Pinus sylvestris) and lime (Tilia vulgaris), were exposed to deionised water over the temperature range 25-65°C. Losses in wet tensile strength and toughness occurred rapidly at temperatures from about 50°C upwards. After about 2 months' exposure pine lost some 10-30% of its tensile strength and 20-60% of its toughness. For lime...
W B Banks, P D Evans
Effect of Scytalidium lignicola on decay resistance and strength of wood
1994 - IRG/WP 94-10061
We reported previously that in laboratory tests, pretreatment of Douglas-fir and Southern Pine blocks with Scytalidium lignicola prevented decay. In the present work, we determined 1) the ability of Scytalidium lignicola to colonize and survive in wood exposed in the field, 2) the decay resistance of blocks removed from previously treated Scytalidium lignicola wood and 3) the effect of Scytalidium...
T L Highley
Bending & tensile properties of vapor boron-treated composites
2002 - IRG/WP 02-40228
North American composites including laminated veneer lumber, oriented strandboard, and medium density fiberboard were treated by vapor boron technology and subsequently tested in static bending. Tensile properties were also determined for the two composite boards. The study was designed as 3 x 2 factorial with three treatment levels and two mill locations for each composite type. In general, mil...
H M Barnes, R J Murphy, B K Via
The effect of extent and location of decay on strength loss in constructional timber
1994 - IRG/WP 94-30039
Radiata pine heartwood billets, 50 x 100 x 1000 mm³ were end-sealed and treated with copper-chrome-arsenate preservative (NZ Type I) to a range of retentions and penetration patterns. Cross-sections, 10 mm thick, were cut from the centre of each billet and used for determination of preservative distribution, for preservative analysis and for decay tests. The decay test consisted of laying samples...
M E Hedley, H Bier