Your search resulted in 927 documents. Displaying 25 entries per page.
The effect on moisture content of water trapped in wood joints
2012 - IRG/WP 12-40613
To predict the service life of a structure, a model where the exposure of a structure is compared to its resistance can be used. Which exposure and resistance parameters that are relevant depend on which materials the structure consist of. This approach, with an exposure and a resistance parameter, is similar to the one used in structural engineering where a load (exposure) is compared to the bear...
M Fredriksson, L Wadsö, P Johansson
Differences between heat treated Pinus pinaster heartwood and sapwood
2012 - IRG/WP 12-40617
Heat treatment is a well known process to improve the durability and dimensional stability of less noble woods. The treatment can be applied for heartwood unlike the traditional treatments based on impregnation due to the difficulty of impregnating heartwood.
Pure sapwood and pure heartwood samples were treated in an oven at 190ºC and 200ºC for 2h, 4h and 6h. Dimensional stability, measured a...
B Esteves, L Nunes, I Domingos, H Pereira
Statistical analysis of durability tests - Part 1: Principles of distribution fitting and application on laboratory tests
2013 - IRG/WP 13-20504
Service life prediction is an important topic in wood research, especially with regard to the Construction Products Regulation (CPR). Both laboratory tests as well as in-service performance testing are therefore essential in combination with proper monitoring and analysis tools. A crucial concept is variability in testing and analysis, especially for a biological material such as wood. The larger ...
I De Windt, J Van den Bulcke, C Brischke, C R Welzbacher, A Gellerich, S Bollmus, M Humar,
Update on "Sandwich" Type Above Ground Field Test Methods
2013 - IRG/WP 13-20506
Our research group has been investigating a number of new designs for above ground field testing to try to provide rapid methods to compare the relative performance of systems in above ground, unprotected exposures. This paper provides an update on what we have found with three variations on a "sandwich" type above ground test arrangement, with comparison to the more traditional lap-joint method ...
A Zahora, L Jin, A Preston
A critical view on early indicators for above ground field performance of wood
2013 - IRG/WP 13-20509
Above ground field tests are quite often a balancing act between the provision of realistic test conditions, reliable statistics, and acceptable long test durations. Within this study we therefore reviewed 543 data sets from above ground field tests performed at 36 different test sites in 8 countries in Australia and Europe. The main objective was to investigate possible correlations between early...
C Brischke, L Meyer, G Alfredsen, P-O Flæte, L Francis, M Hansson, P Larsson Brelid, J Jermer
Quasi-in-situ durability tests on oak timber bridges
2013 - IRG/WP 13-20510
This study aims on developing a method for determination of wood durability on samples taken from real structures in service. Therefore quasi-in-situ durability tests have been conducted exemplarily on timber bridges made from English oak (Quercus robur L.). Drilling cores were found to be a feasible alternative to standard specimens for laboratory durability tests against pure cultures of Basidio...
C Brischke, C J Behnen, M-T Lenz, K Brandt, E Melcher
Changes of fungicidal, mechanical and sorption properties of wood during above ground outdoor exposure
2013 - IRG/WP 13-20513
The aim of this preliminary study was to investigate differences in mechanical, fungicidal, and sorption properties of four different wood species (sweet chestnut (Castanea sativa), common beach (Fagus sylvatica), Norway spruce (Picea abies), and copper-ethanolamine (CuE) impregnated Norway spruce (Picea abies)) that were exposed in the 3rd use class (CEN, 1992) for periods between 4 and 30 months...
N Thaler, M Humar
Accelerated H3 above-ground decay testing
2013 - IRG/WP 13-20520
An above-ground H3 fungal field trial was installed at two sites in Australia and one in New Zealand, as well as in two Accelerated Field Simulators. The aim was to find a method that would shorten the time required for evaluating new preservatives and protection systems. One-quarter H3 retentions were installed, as first results suitable for registration occur when these reach 70% soundness. Twel...
L J Cookson, D Page, T Singh
Predicting the Rate of Decay, and the Potential for Misinterpretation of Proper Scientific Method
2013 - IRG/WP 13-20525
Predicting the rate of fungal attack in wood-based materials and its effect on properties remains the holy grail of wood products pathologists; however, achieving this goal is difficult because of the many variables associated with the process. This paper reviews some of the more important aspects of the decay process in relation to test methodology and then discusses how data are sometimes used b...
B S Goodell, J J Morrell
Performance testing of DMDHEU-modified wood in Australia
2013 - IRG/WP 13-30613
Chemical wood modification with dimethyloldihydroxy-ethyleneurea (DMDHEU) or its derivatives has been researched for many years and shown to be applicable to improve certain wood properties to both solid lumber and wood-based composites. Earlier research proved a high biological resistance of DMDHEU-modified wood against biological degradation in laboratory and field tests in Europe. Due to the ve...
H Militz, J Norton
Preliminary testing of spiroborate esters as wood preservatives
2013 - IRG/WP 13-30614
Fungicide and insecticide properties of boric acid are known since 30’s of the last century, but high solubility and leachability of inorganic borates limit their use for only applications not directly exposed to liquid water. A number of attempts were made to fixate borate salts into the wood structure but this research topic is still up to date and undiscovered. Water insoluble organoboron est...
D Panov, N Terziev
The effects of impregnation with secondary metabolite extracted from Ipe on durability of Japanese cedar and beech wood
2013 - IRG/WP 13-30618
Ipe wood is known for its high durability; it has been widely used in exterior structures that are exposed to the weather. In this paper, to increase the durability of less durable wood, Japanese cedar and beech specimens were impregnated with a secondary metabolite from Ipe. In a previous study, secondary metabolites extracted by a Soxhlet extraction method showed antifungal properties. Therefore...
T Iida, R Konuma, K Kawarada
40 year results from the largest preservative in-ground stake trial conducted in Australia
2013 - IRG/WP 13-30624
The final results from Australia’s largest preservative in-ground stake trial are listed. There were eight test sites, six in Australia and two in Papua New Guinea. The preservatives tested include low and high temperature creosotes, PCP and various water-borne preservatives including CCA and copper chromate. The main timbers examined were sawn Pinus radiata sapwood, sawn Eucalyptus regnans hear...
L J Cookson
Decay resistance of thermally modified Scots pine after 6 years’ exposure above ground
2013 - IRG/WP 13-40624
In the present study the performance of boards treated by ThermoWood process were studied above ground and the results given are based on a “modified” horizontal double- layer test. The base layer of boards was in direct contact with ground and the conditions were much harder than in the standard method. After six years’ exposure clear differences were found between untreated Scots pine and ...
H Viitanen, S Metsä-Kortelainen, A Nurmi, S Jämsä
Effect of the nature of the inert atmosphere used during thermal treatment on chemical composition, decay durability and mechanical properties of wood
2013 - IRG/WP 13-40625
Wood heat treatment is an attractive alternative to improve decay resistance of low natural durability wood species. Nowadays, several types of thermal treatments of wood exist. These treatments differ mainly by the nature of the inert atmosphere used to avoid wood combustion which may correspond to: nitrogen, vacuum, steam or oil. Decay resistances as well as mechanical properties are strongly co...
K Candelier, S Dumarçay, A Pétrissans, M Pétrissans, P Gérardin
Resistance of WPC against wood destroying fungi
2013 - IRG/WP 13-40627
The investigation of biological durability is a fundamental topic to assess the performance of Wood Plastic Composites (WPC) particularly for outdoor applications. In the last years, different test setups based on existing standards on the field of wood as well as the field of plastics were used for WPC. But the test methodologies give different information about the durability of the tested mater...
A Gellerich, S Bollmus, A Krause
Study of UV resistance and natural weathering of coatings on chemically modified wood
2013 - IRG/WP 13-40629
In this study, UV resistance and weathering performance of rubberwood (Hevea brasiliensis) and radiata pine (Pinus radiata) modified with benzoyl chloride and acetic anhydride was studied. Performance of polyurethane based wood coatings on modified wood was also evaluated. Unmodified and chemically modified specimens were exposed to accelerated and natural weathering. Modified and unmodified woo...
K K Pandey, K Srinivas
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
Influence of coatings on water uptake of wood surfaces before and after natural and artificial weathering
2013 - IRG/WP 13-40641
Liquid water absorption of wood surfaces with and without coating, before and after exposure to artificial and natural weathering has been studied. Spruce, oak and sapele samples have been exposed to the cycle of EN 927-6, to the cycle of the Gardner wheel and to natural weathering. Five coatings were tested including solventborne and waterborne, semi-transparent and opaque products. Exposure to w...
L Podgorski, S Collignan, J-D Lanvin
Moisture and Fungal Durability of Wood-Plastic Composites Made With Chemically Modified and Treated Wood Flour
2013 - IRG/WP 13-40648
Evaluating the fungal durability of wood-plastic composites (WPCs) is complicated by the influence of slow moisture sorption. Recently, the American Wood Protection Association (AWPA) Standard Method E10, Testing Wood Preservatives by Laboratory Soil-Block Cultures, was modified to incorporate not only solid wood, but also wood-based composites and WPCs. To simulate long term WPC performance, cond...
B K Segerholm, R E Ibach
Relevance of natural pre-weathering for laboratory decay tests with native, modified, and preservative-treated wood
2013 - IRG/WP 13-20522
The on-going development of new wood protection systems is hampered by the long term field tests currently in use. New accelerated test methods and novel methods for faster and more accurate evaluation of wood protection methods are requested. For both field decay tests and accelerated laboratory decay tests, limitations are imposed. This study is part of the research program ‘WoodBuild’, whic...
A Pilgård, C Brischke, L Meyer
Moisture dynamics of wood – An approach to implement wetting ability of wood into a resistance classification concept
2014 - IRG/WP 14-20557
Within the research programmes WoodBuild and PerformWOOD, wetting ability tests have been conducted with 25 wood-based materials. A first attempt has been made to establish factors for calculating the material resistance of wood materials to be implemented into a design guideline for timber structures. The approach looks promising, but further studies are needed to establish more reliable relation...
C Brischke, C Hesse, L Meyer, S Bardage, J Jermer, T Isaksson
An Overview of Western Red Cedar as a Wood Pole Species
2014 - IRG/WP 14-10815
This paper reviews the characteristics of western red cedar, with particular emphasis on its use in utility poles. Western red cedar naturally grows primarily in British Columbia, Alaska, Washington, Oregon, California, Idaho and Montana. Compared to other commercial softwoods it has low density, increased corrosivity, weaker mechanical properties, high dimensional stability, and high natural dura...
M H Freeman, R Stirling
Performance of recent and old Sweet chestnut (Castanea sativa) wood
2014 - IRG/WP 14-10816
Sweet chestnut (Castanea sativa) hardwood is one of the most durable European wood species. In the present research, various aspects that could potentially influence the durability were elucidated, namely: presence of extractives, ring width, and weathering. Simultaneously, properties of wood, which was in outdoor use for 35 years, were elucidated as well. The results indicate that ring width and ...
M Humar, M Žlahtič, N Thaler
Microbial Community Analysis of Naturally Durable Wood in an Above Ground Field Test
2014 - IRG/WP 14-10826
This paper presents preliminary results of an above ground field test wherein eight naturally durable wood species were exposed concurrently at two sites in North America. Surface samples were taken at regular intervals from non-durable controls and compared to their more durable counterparts. Terminal Restriction Fragment Length Polymorphism was performed to characterize the microbial (bacteria, ...
G T Kirker, S V Diehl, P K Lebow