Your search resulted in 744 documents. Displaying 25 entries per page.
Testing the performance of timber using 27 different field test methods
2013 - IRG/WP 13-20517
Numerous test methods to determine the durability of timber and timber products have been described in relevant literature. However, only some of these methods have been standardized and thus only very few are regularly used for resistance tests in the field. Since results from extensive comparative field studies have shown differences in moisture performance between different test methods, the ai...
L Meyer, C Brischke, J Rieken
Virulence of two Laboratory Test Strains and one Natural Isolate of Rhodonia (Oligoporus) placenta against Thermally Modified Pine and Beech Wood
2013 - IRG/WP 13-20524
Rhodonia (Oligoporus) placenta is known as a relative aggressive basidiomycete fungus against thermally modified timber. In durability lab tests, this often results in a lower durability class, compared to other test fungi. In the reported work, the virulence of three different strains of Rhodonia placenta for untreated and thermally modified timber was determined and compared. Therefore, two lab ...
K Plaschkies, W Scheiding, K Jacobs, N Rangno
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
Moisture distribution in glulam beams with natural cracks observed with CT Scanning before and after rain
2013 - IRG/WP 13-20534
The way cracks in outdoor wooden constructions affect durability is an interesting topic, since a certain amount of cracks can always be found naturally in wood and glued laminated wood. The question in this was, can cracks lead water into the wood and thereby increase the risk for decay and reduce strength and service life. Moisture balance, i.e., water absorption and water distribution were stud...
K Sandberg
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
Copper Coating on Wood: a New Way of Protecting Wood
2013 - IRG/WP 13-30617
Thermal spray metal coating technology was used to apply a thin layer of copper on the surfaces of a number of wood species. The adhesion of metal coating to mahogany, oak, soft maple, spruce, white pine and medium density fibreboard (MDF) was evaluated by pull off adhesion test. The resistance of copper coated wood samples to mildew were assessed in the lab. Also, the decay resitance and water re...
M Nejad, R Shafaghi, L Pershin, J Mostaghimi, P Cooper
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
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
Protective effectiveness of antifouling coatings for wooden boats in the Northern Adriatic Sea
2013 - IRG/WP 13-40634
There are various conventional biocide containing antifouling coatings and some more environmentally friendly paints for boats on the market. However, the question of their performance in accordance with the manufacturers’ statements or guaranties arises. The aim of our preliminary investigation was to state which type of antifouling coating exhibits better effectiveness against fouling organism...
M Petrič, M Humar, J Adamek, B Kričej
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
Durability of alternatives to CCA-treated wood - Results from field tests after 11 years exposure
2013 - IRG/WP 13-30633
The present study was initiated as a consequence of restrictions against the use of CCA-type
wood preservatives in Sweden in the 1990s. New copper-based formulations were introduced on
the market and to some extent, also alternatives to preservative-treated wood, such as thermally
and chemically modified and linseed oil treated wood as well as heartwood of non-tropical
naturally durable wood s...
P Larsson Brelid, M-L Edlund
Estimation of service life of treated wood in ground contact based on early indicators
2013 - IRG/WP 13-20536
A well-known problem with field testing is that it takes a long time before meaningful and reliable results are achieved. Only when a trial has come to an end the so called average life for the samples in a group can be calculated and compared with other samples. The aim of the present study was to investigate if it is possible to get a reasonable and good estimation of the average life long befor...
M Hansson, J Jermer, P Larsson Brelid, N Terziev
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
Natural durability of plantation-grown coast redwood (Sequoia sempervirens) in New Zealand
2014 - IRG/WP 14-10817
There is wide variation in the wood properties of plantation-grown coast redwood in New Zealand. Contributing factors are the seed source, silviculture, growth and age of the trees in the plantation forests. Little is known about how these factors affect the variation of wood properties among and within the trees of New Zealand’s coast redwood forests. Heartwood of plantation-grown coast redwood...
D O’Callahan, T Jones, C Low, C Chittenden
Using hyperspectral imaging to detect and quantify mould and blue stain on coated and uncoated wood
2014 - IRG/WP 14-10822
Hyperspectral imaging has been applied on the surface of samples of coated and uncoated Norway spruce (Picea abies) as a new technique to detect and quantify growth of mould and blue stain fungi. Principal Component Analysis of the hyperspectral images resulted in a clear visualization of the fungi and the amount of mould coverage could be estimated. This indicates that NIR hyperspectral imaging c...
L Ross Gobakken, I Burud, A Flø, K Kvaal, T K Thiis
Durability and Wood Protection for Historic Covered Bridges in the United States
2014 - IRG/WP 14-10829
A majority of the covered wooden bridges in United States were built in the mid -1800’s. These structures represent a unique cultural and technological heritage from that era. Over time, these bridges have been deteriorated by microorganisms and insects or damaged by acts of vandalism and arson. The National Historic Covered Bridge Preservation (NHCBP) Program sponsored by the Federal Highway Ad...
V W Yang, C A Clausen
Variability in durability of some selected South-American wood species
2014 - IRG/WP 14-10831
Within the scope of sustainable forest management one wants to encourage the proper use of lesser known wood species. Therefore the market has to shift from a demand-driven towards a supply-driven market without loss of wood quality. It is generally known that the durability from pith to bark varies thus, affecting the overall durability of wood species. Consequently, a detailed analysis is necess...
I De Windt, P ’t Hooft, J Van den Bulcke, J Van Acker
Moisture performance testing of wood – Practical experiences
2014 - IRG/WP 14-20546
Different methods are used to characterize the moisture performance of wood and to quantify the effect of moisture loads on the resulting service life. These methods can be divided into direct and indirect methods. Furthermore they can be distinguished by characteristics like continuous or periodical measurements and measuring local or global moisture content (MC). Furthermore each measuring metho...
L Meyer, C Brischke, M Kasselmann, C Rösmann
In-ground durability of wood-based products – Comparative assessment of graveyard field tests and terrestrial microcosms
2014 - IRG/WP 14-20538
Traditionally wood durability and the effectiveness of wood preservatives are determined in so-called graveyard tests (according to EN 252 or AWPA E7). For laboratory testing, terrestrial microcosms (TMC) can serve as an alternative. Both tests have been applied for different types of wood-based materials, preservative treated, modified and unmodified wood. However, the usability of laboratory res...
A Soetbeer, L Meyer, C Brischke, P Larsson-Brelid, J Jermer