Your search resulted in 1489 documents. Displaying 25 entries per page.
Dimensional stability and decay resistance of montmorillonite- furfuryl alcohol modified wood
2019 - IRG/WP 19-40856
Poplar (Populus cathayana) wood was impregnated successively by organo-montmorillonite (OMMT; in concentration of 2%) and furfuryl alcohol (FA, in concentrations of 15%, 30% and 50%) in a two-step method to prepare OMMT-FA modified wood. The modified wood samples were characterized using X-ray diffraction (XRD) and field emission scanning electron microscopy (FE-SEM). Moreover, wood physical and a...
L Zhang, J Cao
Improvement of wood decay and termite durability resulting from combined treatments based on borax/phenol-formaldehyde impregnation followed by thermal modification
2019 - IRG/WP 19-40871
This study determined the factors influencing the boron content after leaching of pine blocks impregnated with aqueous solution of phenol-formaldehyde (PF) resin with or without borax and subjected to heat treatment by response surface methodology. An experimental design permits to analyze the effects of heat treatment temperature (150, 185 and 220°C), curing time (5, 12, 5 and 20 hours), resin c...
S Salman, M-F Thevenon, A Petrissans, S Dumarcay, P Gerardin
Durability testing of mass timber building elements: a call for a collaborative trial
2019 - IRG/WP 19-40875
Mass timber buildings have captured the imagination of architects and engineers seeking more environmentally friendly building materials. The mass timber movement has tremendous potential to markedly increase timber use in mid-rise to high rise buildings. With great promise, however, comes great risk. Most mass timber structures that have been built or are being planned use no protective treatm...
J J Morrell
Fungal damages in Norwegian massive timber elements – causes and measures
2019 - IRG/WP 19-40879
Massive wood elements are relatively new in Norway but the use is growing quickly, primarily the use of cross-laminated timber (CLT). Moisture performance of massive timber elements has been examined by some researchers, but more knowledge is needed. There is uncertainty regarding the need for vapour barriers or retarders in roof assemblies, and for practical reasons buildings are rarely assembled...
M S Austigard, J Mattsson
Experimental study on compressive strength performance of cross laminated timber with biodeterioration damage
2019 - IRG/WP 19-40883
The mass timber construction has attracted attention around the world. The reasons are due to the environmental impacts and the potential of the strength performance and quantity of the wood. Nowadays, CLT is one of the most important materials for the timber constructions. If we use CLT as a building material, we should consider the biodegradation risk for long time use. From an estimation of fut...
T Mori, Y Otsubo, R Inoue, M Ikeda, K Kambara, W Ohmura
Different levels of acetylation lead to groupwise upregulation of non-enzymatic wood degradation genes of Rhodonia placenta during initial brown-rot decay
2020 - IRG/WP 20-10958
Rhodonia placenta, often used as a model fungus to represent brown rot fungi, uses a two-stepped degradation mechanism to degrade wood. Regarding the overcoming of wood protection systems the initial degradation phase seems to be the crucial point. A new laboratory test enables the separation of the non-enzymatic oxidative and the enzymatic degradation phases, which has previously been proven chal...
M Kölle, R Ringman, A Pilgård
FTIR analysis of wood blocks decayed by brown-rot fungi
2020 - IRG/WP 20-10959
Calibration curves of the relative lignin contents in Cryptomeria japonica decayed by brown-rot fungi were developed with Infrared Spectroscopy and Klason technique. First, wood decay test was conducted using brown-rot fungi (Fomitopsis palusris, F. pinicola, Wolfiporia cocos, Gloeophyllum trabeum, and Neolentinus suffrutescens) and white-rot fungus (Trametes versicolor) was used as a comparison. ...
R Kondo, Y Horikawa, R Kose, M Yoshida
Effect of long-term immersion in fresh and salt water on mould growth on Scots pine (Pinus Sylvestris L.) wood
2020 - IRG/WP 20-10962
Wood exposed outdoors will eventually be degraded by fungi, depending on exposure and material characteristics. Numerous wooden constructions in the Røros municipality have existed since the 17th century, but wood used in recent repairs have decayed faster than expected. Before 1970 timber was mainly transported by log driving or rafting, and the logs were immersed in water for longer or shorter ...
M Sand Austigard, J Mattsson
Performance of naturally durable decks after 15 years of field exposure
2020 - IRG/WP 20-10963
A decking test of Canadian species considered to be naturally durable was inspected after 15 years of exposure at test sites in Ontario and British Columbia. Based on the materials used in this experiment, Douglas-fir and yellow cypress had the greatest decay resistance, followed by eastern white cedar and western redcedar, and then by western larch and tamarack. All materials tested were more dur...
R Stirling, D Wong
Observed and projected changes in the climate based decay hazard of timber in the United Kingdom
2020 - IRG/WP 20-20665
The risk of microbiological attack on wood is determined by both material and climatic factors and indeed the hazard for a component is based on its intrinsic durability and the conditions in which it is used. The use of wood and organic materials in construction is increasing but ultimately all these materials will be susceptible to microbiological attack. The Scheffer Climate index applies clima...
S F Curling, G A Ormondroyd
Limiting Polysaccharide Motion Protects Wood From Decay
2020 - IRG/WP 20-40890
It is well known that chemical modifications to improve decay resistance also reduce the equilibrium moisture content (EMC) of wood. The mechanism of this action, however, has been the subject of much debate. Several groups have suggested that decay resistance is a result of lower diffusion rates of fungal degradation agents through the wood cell wall. A recent paper explained the fundamental prin...
C G Hunt, S L Zelinka, J E Jakes
Long-term field exposure of wood-plastic composites processed on a commercial-size extruder
2020 - IRG/WP 20-40894
Wood-plastic composites (WPC) contain wood fiber (or flour), thermoplastics and additives and are exposed to UV light, moisture, and biological deterioration in outdoor installations. Accelerated laboratory tests can help to predict the durability of WPCs, but long term evaluations are needed to validate these results. Field exposed above-ground WPC deck boards (30.5 x 139.7 x 609.6 mm) and in-gro...
R E Ibach, C M Clemmons, N M Stark
Biological durability of sapling wood
2020 - IRG/WP 20-10967
Sapling-wood products from different wood species such as willow (Salix spp.) and Common hazel (Corylus avellana) are frequently used for gardening and outdoor decoration purposes. Remaining bark is suggested to provide additional biological durability. Even for temporary outdoor use it seemed questionable that durability of juvenile sapwood can provide acceptably long service lives of horticultur...
C Brischke, L Emmerich, D G B Nienaber, S Bollmus
Modelling decay rates of timber exposed above ground on four different continents
2020 - IRG/WP 20-20670
Durability performance data from an international decking trial were analysed to explore relationships with climate variables, particularly those related to temperature and rainfall. Matched decking samples of slash pine (Pinus elliottii) sapwood and heartwood, spotted gum (Corymbia citriodora), Norway spruce (Picea abies) and Scots pine sapwood (Pinus sylvestris) were exposed to the weather above...
L P Francis, J J Morrell, C Brischke, P B Van Niekerk, J Norton
Impact of fungal decay on the bending properties of wood
2020 - IRG/WP 20-20671
Wood used outdoors is generally prone to fungal degradation, and its impact on the structural integrity of wood is an immanent factor for service life planning with timber. Wood decayed to very small mass losses can suffer from a significant reduction in mechanical strength and elastic properties. Hence, the latter are preferred indicators to detect decay in wood durability studies. Numerous previ...
S Bollmus, P B van Niekerk, C Brischke
The role of specimen format in wood durability testing
2020 - IRG/WP 20-20672
The experimental basis for testing the biological durability of wood are often incubation experiments with wood-destroying basidiomycetes. Numerous parameters can affect the mass loss by fungal decay (MLF) in laboratory durability tests and therefore being decisive for the resulting durability classification. Among others, the dimension of the wood specimen and the time of incubation impact on fun...
C Brischke, L K Grünwald, S Bollmus
A summary of decay performance with citric acid and sorbitol modification
2020 - IRG/WP 20-40898
Application of wood-based products as construction materials is one piece of the big puzzle to mitigate climate change. Wood is susceptible to biological deterioration. Environmentally motivated legislation is making the use of biocides less attractive from a commercial perspective. Ideally, a wood modification technology should be of low cost, water based and make use of thermal curing. This rese...
G Alfredsen, E Larnøy, G Beck, J Biørnstad, L R Gobakken, C A S Hill, A Treu
Durability of acetylated Radiata pine: Laboratory tests and performance in practice
2020 - IRG/WP 20-40899
Wood acetylation is an established process to enhance biological durability and dimensional stability of lower valuable wood species without the use of biocides. Acetylated Radiata pine (ACCOYA® wood) has been on the market for more than 10 years now, starting in 2007.
Numerous lab tests have confirmed the high durability of acetylated Radiata pine. Here, additional data with four Radiata pine ...
K Jacobs, W Scheiding, B Weiß
Sterilization of Large Timbers during Preservative Treatment: How Quickly We Forget
2020 - IRG/WP 20-40902
Air seasoning is a common method of moisture management in utility poles and is done de facto during pole storage prior to treatment. However, extended air drying prior to treatment encourages fungal attack and can facilitate establishment of decay fungi in poles before a protective preservative barrier is applied. This problem can be mitigated by proper air-seasoning methods coupled with heat ste...
G Presley, J Cappellazzi, M Konkler, K Maguire, R Nelson, J J Morrell
Assessing the risk of marine borer attack of the timber trestles and decay of timber above the intertidal zone of the Barmouth Viaduct
2021 - IRG/WP 21-10974
The Barmouth Viaduct is a Grade II* listed structure which carries the single track of the Dovey Junction to Pwllheli line and footway over the Mawddach estuary. It is in a marine environment where timber below the high tide mark is at most risk in Use Class 5 and all timber above in Use Class 3.2, permanently exposed to the risk of wetting. The structure consists of a timber trestle viaduct of ...
J R Williams
Effect of MVOC exposure on mycelial growth of wood rotting fungi
2021 - IRG/WP 21-10977
It is well known that wood rotting fungi produce microbial volatile organic compounds (MVOCs) as metabolites. In our previous studies, we have found that some MVOCs produced by wood rotting fungi are common to fungal species tested in the studies, while others are specific to each species. Furthermore, it has been also shown that each wood rotting fungi do not always produce the same type of MVOCs...
S Horikawa, R Konuma, M Yoshida
Decomposition and metabolism of gaseous COS by wood rotting fungi
2021 - IRG/WP 21-10978
Previous studies on physiology of wood rotting fungi have mostly focused on the metabolisms of carbon and nitrogen sources. On the other hand, despite of the biological importance of minerals such as sulfur, our knowledge of their metabolic systems is limited. The sulfur source for wood-rotting fungi has been thought to be water-soluble sulfur compounds such as sulfate esters and cysteine, which a...
R Iizuka, O Iwao, Y Katayama, M Yoshida
The iron reduction by chemical components of wood blocks decayed by wood rotting fungi
2021 - IRG/WP 21-10979
Brown-rot fungi, a group of wood rotting fungi, is well known to be one of major microorganisms that cause the deterioration of wooden buildings in Japan and have been considered to use chelator-mediated Fenton (CMF) reaction in concert with hydrolytic and redox enzymes for degradation of wood cell wall. CMF can be described as a non-enzymatic degradation system that utilizes hydroxyl radicals pro...
R R Kondo, Y Horikawa, K Ando, B Goodell, M Yoshida
Studies on the material resistance and moisture dynamics of Douglas fir and Sitka spruce from Slovenia
2021 - IRG/WP 21-20677
Wood in outdoor applications is subject to various decomposition factors. Wood degradation can be prevented by construction details, biocide protection of wood, wood modification, or selection of naturally durable wood species. Unfortunately, the majority of timber species in Europe do not have naturally durable wood. Imported tree species represent a new pool from which we can draw wood species w...
M Humar, B Lesar, D Krzisnik, E Kerzic, R Brus
Estimation of residual compressive strength on cross laminated timber with biodeterioration damage
2021 - IRG/WP 21-40918
CLT is susceptible to biodeterioration such as fungal decay and termite attack during long-term use for buildings. It is necessary to know the residual strength performance of biodegraded CLT for estimating future performance and aging of CLT. In this study, compression tests of CLT damaged by brown rot fungi and termites were conducted to clarify the relationship between residual strength and mas...
R Inoue, T Mori, K Kambara, W Ohmura