Your search resulted in 47 documents. Displaying 25 entries per page.
Service life prediction of wooden components - Part 3: Approaching a comprehensive test methodology
2011 - IRG/WP 11-20464
This paper is the third in a series on 'service life prediction' of wooden components and should be considered as a discussion paper. The authors tried to analyze the topic with a look from a distance and comment sometimes with a smile on the current controversial discussion about SLP issues. Nevertheless, the viewpoints of different groups, such as natural scientists, engineers, approva...
C Brischke, C R Welzbacher, L Meyer, T Bornemann, P Larsson Brelid, A Pilgård, E Frühwald-Hansson, M Westin, A O Rapp, S Thelandersson, J Jermer
Improving our understanding of moisture and other durability-related properties of wood in building envelope performance prediction
2011 - IRG/WP 11-20468
Building science has become an increasingly important field in recent years with rapid changes in construction methods, building materials and consumer expectations. The field has also been brought to prominence by a few large-scale premature building envelope failures in a few regions across the world. Considerable effort has been put into developing hygrothermal models to simulate heat, air, vap...
Jieying Wang, P Morris
Decay initiation in plywood, OSB and solid wood under marginal moisture conditions
2011 - IRG/WP 11-20469
Hygrothermal models are increasingly used as research tools by building scientists and and design tools by designers to simulate heat, air, vapour, and water movements within and through building envelope and even to predict the consequences in terms of mould/decay growth and metal corrosion. This work was designed to generate data on decay initiation under marginal moisture conditions to support...
Jieying Wang, P Morris
Effects of Heat-Treatment in Hot Water and Steam Mediums on Gas Permeability of Beech Wood
2011 - IRG/WP 11-40557
Heat-treatment, as a major method of wood modification, improving dimensional stability, and natural durability, has been studied greatly from different aspects. The effect of heat-treatment on gas permeability, as an important physical property of wood, in two different mediums of hot water and steam, as well as in two buffers of 7 and 8, is the main topic of the present study. Hydrothermal treat...
H Reza Taghiyari, A Talaei, A Karimi
Performance of Creosote/Chlorothalonil Preservatives
2011 - IRG/WP 11-30580
The addition of chlorothalonil to P2 creosote was found to increase the durability of southern pine in a series of ground contact stake tests. At retentions lower than those specified in the AWPA Standards, performance was increased when the creosote was amended with chlorothalonil. This indicates that lower creosote retentions may be required for as good or better ground contact when the amende...
H M Barnes, M G Sanders, G B Lindsey, T L Amburgey
Study on the Effect of Combined Nanosilver-Hygrothermal Treatment on Wood Properties
2012 - IRG/WP 12-40581
In this study, the impregnation process with nanosilver solution, before hygrothermal treatment was carried out to investigate its effect on some physical and mechanical properties of Iranian beech (Fagus orientalis Lipsky) and Russian imported spruce (Picea abies). Wood specimens were impregnated with nanosilver solution (400ppm) in an impregnation tank under pressure of 0.25 Mpa, for 20 minutes....
G Rassam, H Reza Taghiyari, A Karimi, B Jamnani, M Ebrahimi
Study on the Effect of Combined Nanosilver-Hygrothermal Treatment on Wood Properties
2012 - IRG/WP 12-40581
In this study, the impregnation process with nanosilver solution, before hygrothermal treatment was carried out to investigate its effect on some physical and mechanical properties of Iranian beech (Fagus orientalis Lipsky) and imported Russian spruce (Picea abies). Wood specimens were impregnated with nanosilver solution (400ppm) in an impregnation tank under pressure of 0.25 Mpa, for 20 minutes....
G Rassam, H Reza Taghiyari, A Karimi, B Jamnani, M Ebrahimi
Investigation of Nanocopper-Hygrothermally Treated Wood Properties
2013 - IRG/WP 13-40644
Nanometals with high thermal conductivity can be considered as modifiers, especially in thermal modification of wood. This study was aimed to investigate some physical and mechanical properties of nanocopper impregnated Iranian beach (Fagus orientalis Lipsky), which was hygrothermally treated. For this purpose, nanocopper solution (400 ppm) was used for impregnation process. Hygrothermal treatment...
G Rassam, B Jamnani, A Faraji Heris
Emerging function for a glutathione transferase in response to wood extractives toxicity
2014 - IRG/WP 14-10824
The first steps of wood degradation by fungi lead to the release of toxic compounds known as extractives. To better understand how lignolytic fungi cope with these products, a transcriptomic analysis of Phanerochaete chrysosporium genes was performed in presence of oak acetonic extractives. The most up-regulated genes relate to nutrition, nucleic acid modification, gene regulation, signalling and ...
A Thuillier, K Chibani, A Deroy, S Dumarçay, P Gérardin, A Kohler, J-P Jacquot, E Gelhaye, M Morel-Rouhier
Development of decay hazard maps based on decay prediction models
2016 - IRG/WP 16-20588
Durability plays a very central role in timber engineering, especially when working with wood in use class 3 and above where the risk of decay is high. As one of the primary decay influencing factors, the external condition, i.e. the local climate, is often graded by some type of climate index value. Predominately, climate indices are based on a direct relationship between weather data and decay. ...
J Niklewski, E Frühwald Hansson, C Brischke, D Kavurmaci
Hygrothermal performance of ventilated wooden cladding
2016 - IRG/WP 16-40733
The risk for an attack of wooden claddings by decay and discolouring fungi strongly depends on the moisture and temperature conditions in the building envelope. The design of the cladding has a major influence on its hygrothermal performance. In the present study, different wooden ventilated cladding designs were investigated at a test house in Mid-Norway for four years. The objective was to incre...
K Nore, U Hundhausen
An experimental study of mould growth and wood decay in timber frame walls
2017 - IRG/WP 17-20623
This paper deals with parameters related to the occurrence of mould growth and wood decay in timber frame walls. In a first part, the hygrothermal conditions inside a timber frame wall finished with brick veneer cladding are analysed to get an idea of possible moisture related problems. It is shown that, based on the VTT mould prediction model, there is a mould risk on the interface between the in...
M Vanpachtenbeke, J Van den Bulcke, I De Windt, J Langmans, S Roels, J Van Acker
Response of the symbiotic flagellate protists community of subterranean termites to sublethal amounts of biocides
2018 - IRG/WP 18-10911
Subterranean termites are quite efficient at extracting nutrients from lignocellulose. Their ability relies not only on the digestive tract physiology but also on symbiotic relationships established with flagellate protists and bacteria. This work aimed to screen the response of the flagellate protists community of the subterranean termite Reticulitermes grassei Clément to the ingestion of differ...
S Duarte, T Nobre, P Borges, L Nunes
Response of Terminalia mantaly H. Perrier wood to beetles tunneling in Southern Nigeria
2018 - IRG/WP 18-10918
Terminalia mantaly (TM), is extremely susceptible to beetles attack, as evidenced by the many scars and/or tunnels on nearly all the trees in the Southern Nigeria. However, information on the responses of wood to insects tunnelling is poorly known for tropical species. To examine the response of TM stem wood to beetles tunnelling in the University of Port Harcourt, we scheduled field observational...
G A Adedeji, U Zakka, A A Aiyeloja, A I Ochuba
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
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
The influence of chemical compounds on wood cell wall to surface cracks
2020 - IRG/WP 20-40908
Degradation due to cracking and dimensional changes caused by drying, have a significantly negative impact on the preservation and durability of wood. Therefore, the prevention of surface cracking, which tends to occur during the drying process, is vital. High temperature set drying is one of the most effective methods for preventing wood surface cracking. It begins with softening the wood at a hi...
R Suzuki, Y Mori, K Yoshihiro, K Yamashita, M Kiguchi
Studies into the effect of soil type and soil layer on the in-ground decay of European beech
2022 - IRG/WP 22-20681
In this study, European beech (Fagus sylvatica L.) specimens were exposed to three different soil types; Podsol (Podzol), Braunerde (Cambisol), and Pararendzina (Regosol), in adapted terrestrial microcosm (TMC) tests according to CEN/TS 15083-2 (2005). Soils were sampled (250 mm deep) from field sites and separated into their constituent layers to deliver three TMC setups; mineral soil layer only ...
B N Marais, S Kovacs, M Jansen, C Brischke
Steam Pre-conditioning Treatment Prior to Acetylation: Impact on Dimensional Stability, Moisture Response Behaviour, and White-Rot Fungal Resistance of Hevea brasiliensis and Mitragyna ciliata Wood
2022 - IRG/WP 22-40930
The effect of steam pre-conditioning treatment on the dimensional stability, moisture response behaviour, and durability against white-rot fungus P. chrysosporium of acetylated Hevea brasiliensis and Mitragyna ciliata wood species were assessed. Defect-free specimens of both species from the top, middle, and base positions were selected, prepared according to ASTM D143-09 & ASTM D-2017 standards a...
E Uchechukwu Opara, J Mayowa Owoyemi, J Adeola Fuwape
Simulations of microclimates for wood-decaying fungi in the built environment using environmental analysis
2023 - IRG/WP 23-20703
Simulations of fungal decay risk were run on two similar building geometries exposed to typical annual climate conditions of two different geographical locations, Brunswick (Germany) and Cairns (Australia). The simulations were conducted to capture the effect of wind-driven rain and solar irradiation exposure over nodes of the common building geometry. The moisture content and temperature variatio...
P B van Niekerk, J Niklewski, S H Hosseini, B N Marais, I Frimannslund, T Kringlebotn Thiis, C Brischke
Changes in decay risk of wood in ground contact over Europe, from analysis of historic climate conditions
2024 - IRG/WP 24-41008
Changing climate conditions will affect global temperature and precipitation patterns, shifting some geographical areas into states that are more suitable for fungal wood decay. Climate normals, which are taken over a 30-year period, capture vast spatial and temporal variations in these conditions and comparing these can show changes over time. Importantly, being able to identify locations that ha...
P B van Niekerk, B N Marais, G Alfredsen, C Brischke
Determining the minimum water vapor permeability of exterior wood coatings by means of hygrothermal and decay models
2024 - IRG/WP 24-20717
The objective of this study was to determine the minimum water vapor permeability of exterior wood coatings for log homes using hygrothermal and decay modeling. The approach is based on a worst-case scenario assumption, namely a moisture trap at a given wood moisture content in a coated wall log. The minimum limit of vapor permeability of the coating system was determined by simulating the time re...
U Hundhausen, S Ullah, D Kraniotis