Your search resulted in 698 documents. Displaying 25 entries per page.
Wet and dry adhesion of coatings on modified and unmodified wood: comparison of the pull-off test and the cross-cut test
2010 - IRG/WP 10-40524
The objective of this paper is to study the influence of several types of modification (acetylation, furfurylation, thermal modification) on coatings adhesion and to compare two methods of assessing the adhesion: the cross-cut test and the pull-off test both tested in dry and wet conditions. The study also investigates the effect of other parameters of the wood substrates on adhesion like the ring orientation, the density, the surface preparation and conventional preservatives treatments. It has been shown that the pull-off test is more sensitive than the cross-cut test and gives more information about the influence of the substrate. For both tests wet adhesion is lower than dry adhesion. Compared to the reference, there is no improvement in the dry adhesion due to the different modifications, treatments or variations of the substrates. For some coatings a decrease in dry adhesion is observed on furfurylated and thermally modified wood.
L Podgorski, G Grüll, M Truskaller, J D Lanvin, V Georges, S Bollmus
Wet and dry adhesion of coatings on modified and unmodified wood: influence of 18 months of natural weathering on the pull-off test and cross-cut test results
2011 - IRG/WP 11-40569
The objective of this paper is to study the influence of several types of modification (acetylation, furfurylation, heat treatment) on coatings adhesion after 18 months of natural weathering according to EN 927-3 in Vienna (Austria). The paper compares two methods for assessing the adhesion: the cross-cut test (EN ISO 2409) which is the conventional method used and recommended in EN 927-3 and the pull-off test specified in ISO 4624. The influence of the test condition (dry or wet) is also investigated. Results are part of the WoodExter project funded by the Woodwisdom-net and complete document IRG/WP 10-40524 which presented adhesion results before weathering.
L Podgorski, G Grüll, M Truskaller, J D Lanvin, S Bollmus
Susceptibility of antisapstain fungicides to rain wash-off
1994 - IRG/WP 94-30046
Results of trials using miniature timber packets and simulated rain wash-off are described. Six fungicidal actives in five commercial antisapstain formulations were involved, and a clear influence of rainfall timing after antisapstain treatment was demonstrated. Differences between actives and formulations were most marked where water-spray was applied in the first hour after treatment, though even when applied after a 48 hour delay there were up to ten-fold differences in the percentages mobilised. Possible mechanisms of fixation are discussed in relation to known formulation properties. Results from a full scale trial at a sawmill are also given, and comparison made with the small-scale packet experiments. It is concluded that the results were very similar. The work is extrapolated to the 'real-life' sawmill situation, and conclusions drawn as to the likely results of heavy rain exposure at different times after fungicidal treatment of timber.
R N Wakeling, D J Cross, D R Eden, P N Maynard
Re-sealing cut ends of envelope-treated softwood framing timber to protect against damage by the Australian subterranean termite Coptotermes acinaciformis: A revisitation
2006 - IRG/WP 06-20335
The claim that Australian Coptotermes acinaciformis (Froggatt) do not appear to initiate damage on timber from the end grain, thereby negating the need for treating exposed cut ends of softwood framing material (35 ? 90 mm) which has a repellent Tanalith? T envelope, was further investigated. Specimens of commercial Pinus radiata D.Don framing timber (untreated) and Pinus elliottii Englem. (untreated and envelope-treated) were partially clad in fine stainless steel mesh. Clad and unclad specimens were exposed to C. acinaciformis near Townsville, Australia, for four months. Results showed that this species of termite can damage timber from the end grain, including exposed cut ends of envelope-treated material. Differences between these and other test conditions (where C. acinaciformis did not damage timber from the end grain) are discussed. Clearly, outcomes from laboratory and field studies with preservative-treated materials are dependent upon experimental conditions. The amount of feeder material offered in a given method can strongly influence the termite response. Further investigation is required to standardise this aspect of conditions in protocols for assessment of wood preservatives.
B C Peters, M Lenz, J W Creffield
Development of accelerated decay test for CLT using a fungus grown on agar medium
2019 - IRG/WP 19-20664
CLT is a large-scale wooden board which consists of several layers of sawn lumber stacked in altering directions. Therefore, a lot of large cross sections appear on all narrow faces of CLT. As water penetrates easily into timber from cross section, wooden material whose cross section is exposed to water in in a usage environment is susceptible to deterioration by organisms. Wood deterioration organisms, such as fungus also easily penetrates timber from the cross section. The large cross sections of CLT would be weakness against deterioration by organisms. Therefore, the cross sections of CLT must be considered when evaluating its durability of CLT. To develop the accelerated decay test for CLT regarding with the cross sections, we examined the acceleration of deterioration by contacting untreated CLT samples of the dimension 150×150×150 mm with fungus (Fomitopsis palustris) grown in agar medium in plastic container for 3 and 6 months. As the results, the mass loss of the samples attached with two containers (samples sandwiched between two containers) was higher than of with one container. The mass loss of the samples exposed for 3 months with two containers was lower than that of the samples exposed for 6 months with one container. The method with two containers is considered to be more suitable for the accelerating decay test of CLT.
T Miyauchi, K Kambara, W Ohmura, T Mori, H Matsunaga, N Hattori
Post-layup protection of mass timber elements in above ground protected exposures: 2-year results
2022 - IRG/WP 22-30766
Mass timber has seen increased use as a building material for low and mid-rise construction in recent decades. The durability of mass timber elements has not been fully examined and the effects of wood destroying organisms on this these materials merits attention. The effectiveness of currently labeled soil termiticides and passively applied biocides at post-construction or as remedial agents needs to be evaluated for mass timber used in structures, particularly in areas with elevated risk of termite attack. The ability of soil insecticidal drenches or spray-on insecticide/fungicide treatments for protecting mass timber in service was assessed with a modified AWPA Standard E21 above-ground test using three ply Douglas-fir or southern pine cross-laminated timber as well as Douglas-fir mass plywood panels. Samples of each material (305 x 102 x 102 mm) were installed in an above ground protected test at the Harrison Experimental Forest (HEF) (Saucier, Mississippi) in September, 2019. Six replicates of five treatments including soil termiticide, no treatment, spray-on borate at initiation, borate rods and remedial treatment, using spray on borate of attacked material after two years, were tested. Samples were left undisturbed for two years and then examined and rated. Near surface moisture content increased to levels approaching the fiber saturation point over the two-year non-disturbance period. Untreated control samples were attacked by both decay fungi and termites. Samples treated with borates at test initiation showed limited decay or termite attack. Soil termiticide treated plots showed no sign of termite attack, but some samples had heavy decay compared to non-soil termiticide treated plots.
M E Mankowski, T G Shelton, G T Kirker, J J Morrell
Programme section 2, Test methodology and assessment
1997 - IRG/WP 97-20126
Progress report on co-operative research project on L-joint testing
1983 - IRG/WP 2192
A F Bravery, D J Dickinson, M Fougerousse
A comparison of soft rot, white rot and brown rot in CCA, CCP, CCF, CCB, TCMTB and benzalkonium chloride treated Pinus radiata IUFRO stakes, after 9-15 years exposure at five test sites in New Zealand
1991 - IRG/WP 1485
The aim of this study was to determine if decay type varies significantly between five field trial test sites of different soil type, aspect and climate in 9-15 year old, replicate CCA, CCF, CCP. CCB, TCMTB and AAC treated IUFRO stakes. A visual on-site assessment of decay type on every test stake was made and observations confirmed by microscopical examination. Regression analyses were used to determine significant differences of percentage frequency of occurrence of each rot type between sites and preservatives. Large differences in percentage frequency of occurrence of rot type were evident between sites. One site was dominated by brown rot (85%) and two were dominated by soft rot (99 and 91%). The fourth site had intermediate proportions of brown rot (40%) and soft rot (71%) but had the second highest occurrence of white rot (32%) (highest = 37%; lowest = 11%). The fifth site was distinct in that a large proportion of stakes (69%) had both well established brown rot and soft rot. Stakes at the other four sites tended to have only one rot type. Some highly significant preservative effects were also found. Possible causes of these differences are discussed in terms of inter-site soil type, climate and other differences.
R N Wakeling
Wood preservatives: Field tests out of ground contact. Brief survey of principles and methodology
1976 - IRG/WP 269
This paper contains the following spots: 1.: The general need for field tests. 2.: Interests and limits of field tests in ground contact. 3.: Various methods in use for out-of-ground contact field tests. 4.: Fungal cellar tests are they an alternative to above-ground decay exposure tests? 5.: Conclusions.
Collaborative soft rot tests. Names and addresses of collaborators
1973 - IRG/WP 231
A suggested method to test the toxicity of wood preservatives towards the house longhorn beetle
1977 - IRG/WP 275
This method was developed in the Institute for Wood Technology in Sarajevo, Yugoslavia and is used to get quick information on the toxicity of wood preservatives against house longhorn beetle (Hylotrupes bajulus). The method can be used for superficially treated or deeply impregnated wood blocks, and by using small or normal size test material it can be used as a laboratory or field test, and also for accelerated infestation of test material out of ground contact. The paper is given to the International Research Group on Wood Preservation as a suggested method which could possibly be used as a standard. Only the laboratory test method is described.
IRG/COIPM INTERNATIONAL MARINE TEST - to determine the effect of timber substrate on the effectiveness of water-borne salt preservatives in sea-water. Progress Report 2: Report of treatment and installation in Australia
1978 - IRG/WP 440
The purpose of this test and the procedures to be followed have been fully set out in documents distributed by the International Research Group on Wood Preservation and numbered IRG/WP/414 and IRG/WP/420. The prescriptions set out in these two documents have been closely followed.
Field test evaluation of preservatives and treatment methods for fence posts
1985 - IRG/WP 3347
This work presents the field test results after fifteen years exposure of Eucalyptus saligna fence posts treated with six different preservatives and five treatment methods. All the combinations with oil-borne preservatives presented the best results and among the waterborne preservatives, the fence posts treated by immersion method were with the lowest performance in the field test.
G A C Lopez, E S Lepage
A rapid field bioassay technique with subterranean termites
1983 - IRG/WP 1188
Details are summarised of a field procedure which is designed to ensure continuous exposure to a replenishing termite biomass. After pre-baiting to determine the presence and identification of a termite hazard, test specimens (35 x 35 x 250 mm³) are installed vertically in the ground adjacent to and in contact with bait specimens of the same dimensions and interconnected by susceptible feeder strip.
C D Howick, J W Creffield
Utilization of curcumin for detection of presence of boron in wood
1982 - IRG/WP 3191
It has been shown that curcumin is not a reliable reagent for detecting boron in wood that has been attacked by fungi
Performance of treated fence posts after 6 years in five test plots in the State of Sao Paulo - Brazil
1976 - IRG/WP 376
Fence posts treated with creosote, pentachlorophenol and creosote/ pentachlorophenol mixtures showed good performance after 6 years of exposure in five test plots located in the State of Sao Paulo - Brazil. Good results were also achieved with copper sulphate/sodium arsenate and copper sulphate/potassium dichromate mixtures. Fungi and termites were the main destroying agents found attacking the posts.
M S Cavalcante
How to Document the Performance of Super-Critical Treated Wood in above Ground Situations?
2005 - IRG/WP 05-20316
The paper presents practical experiences from the preparation of a new preservative treated wood product for introduction to the market. The product in question is Superwood™, which is treated with organic biocides using CO2 in a supercritical state as a solvent. The question is how to evaluate the performance of a new product such as Superwood™ in order to get an acceptance on the market and fulfil the formal requirements. In the European Union countries, the EN 599-1 is the standard that needs to be complied when approving a new product for the market, but it only focuses on the toxic limit against representative decay fungi according to EN 113. However, decay test, above ground and other forms of field tests are optional, this is not in line with the traditional test philosophy in the Scandinavian countries. The open question is to which extent treatment to the level of the toxic threshold value also ensures a long service life and expected performance of the treated commodity. Superwood™ is evaluated using a strategy, in which basic laboratory tests are done to get the toxic value (according to EN 599-1) and in addition a number of field tests are done including accelerated testing in the tropics. These tests are focussed on the evaluation of the performance criteria such as durability and service life and maintenance requirements. These questions must be answered by the producer without having a full record of performance test for their new products. A short status on the test performed on super-critical treated wood (Superwood™) is presented. Based on a comparison between field test in Scandinavia and in the tropical Malaysia a service life of more than 25 years for a specific supercritical treated product is estimated. It is stated that the existing European standardisation system is insufficient when it comes to service life prediction. A number of important questions need to be addressed by the European standardisation system as soon as possible because the market and the public opinion change quickly due to environmental concern.
N Morsing, A H H Wong, F Imsgard, O Henriksen
Influence of different fixation and ageing procedures on the leaching behaviour of copper from selected wood preservatives in laboratory trials
2003 - IRG/WP 03-20264
The paper focuses on the role of different parameters, such as fixation, sample size, wood species, and leaching in internationally standardized ageing procedures for wood preservatives from Europe, Japan and the United States. The leaching protocols used were EN 84, JIS K 1571 and AWPA E11 protocols. The wood species were Scots pine, Sugi and Southern Yellow Pine respectively. Three types of commercially important copper-based wood preservatives were used as model formulations, namely copper/copper-HDO, ammoniacal copper/quat and CCA. The most important factors determining the extent of copper leaching in the different lab trials were the sample size (volume/surface ratio) and the fixation conditions prior to leaching. On the other hand, the wood species and the leaching protocol itself were found to have only minor influence on the copper leaching rate in the test methods included in this study.
J Habicht, D Häntzschel, J Wittenzellner
Developments in the protection of wood and wood-based products
1980 - IRG/WP 340
Technology is playing an increasingly important role in the field of wood protection. This current review highlights how modern techniques have provided greater insight into the biological and physical processes affecting the durability of wood and wood-based products. Emphasis is also given to developments in preservative testing methodology and to the encouraging changes towards both the correct use of timber and the improvement of Standards and Codes of Practice. A final section, on recent technical developments in wood preservation, considers subjects ranging from an evaluation of new specific biocides to methods of increasing the permeability of refractory timber species.
J M Baker
IRG Working Group II. Co-operative leaching test (letter to collaborators)
1974 - IRG/WP 240
J W W Morgan
Testing of wood preservatives against marine borers (Part 1). Method of testing wood preservatives against marine borers (Part 2)
1971 - IRG/WP 37
P C Trussell, C C Walden
IRG/COIPM INTERNATIONAL MARINE TEST - to determine the effect of timber substrate on the effectiveness of water-borne salt preservatives in sea-water. 2nd Interim Report
1981 - IRG/WP 477
Three reference wood species - Alstonia scholaris, Fagus sylvatica and Pinus sylvestris, untreated and treated with 3%, 6% and 10% CCA and CCB solutions were supplied to all participants for submergence at local sites. Regular examination of samples is being carried out - 6 months, 12 months and then annually for 7 years.
R A Eaton
Protocol for evaluation and approving new wood preservative
1985 - IRG/WP 2159
M E Hedley, J A Butcher
The proposal for the method of testing the phytotoxic effect of wood preservatives
2000 - IRG/WP 00-50163
Four methods of testing the phytotoxic effect of wood preservatives are proposed as the unified test by: - direct application of the preservatives to the test plants by spraying; - direct application of the preservative to the soil substrate; - indication plants growing in the vicinity of treated wood; - seed germination rate on the treated substrate.
J Wazny, P Witomski