Your search resulted in 3189 documents. Displaying 25 entries per page.
Weathering of Wood Modified with the N-Methylol Compound 1,3‑dimethylol-4,5-dihydroxyethyleneurea (DMDHEU)
2009 - IRG/WP 09-40467
Scots pine (Pinus sylvestris L.) sapwood boards were treated with a methylated 1,3‑dimethylol-4,5-dihydroxyethyleneurea (mDMDHEU) causing weight gains of approx. 25% and exposed to weathering for 18 months. Compared to untreated boards, treatment with mDMDHEU reduced surface discoloration mainly caused by staining fungi. Boards treated with mDMDHEU exhibited clearly lower moisture content th...
C Mai, Yanjun Xie, A Krause, K Urban, P D Evans, K Richter, H Militz
Service life prediction of wooden components – Part 1: Determination of dose-response functions for above ground decay
2010 - IRG/WP 10-20439
Scots pine sapwood (Pinus sylvestris L.) and Douglas fir heartwood (Pseudotsuga menziesii Franco) specimens were exposed in double layer field trials at 24 different European test sites under different exposure conditions (in total 28 test sets). The material climate in terms of wood moisture content (MC) and wood temperature was automatically recorded over a period of up to eight years and compar...
C Brischke, A O Rapp
Impact of climate change on wood deterioration - Challenges and solutions for cultural heritage
2010 - IRG/WP 10-20441
Deterioration of wood in cultural assets follows the same physiological mechanisms as in modern structures. Therefore rules and data for prediction of service life derived from old wooden structures can be used to model the service life of recent wooden structures and vice versa. The latter is done in this paper: From experimental test set ups in the field spread over Europe, climatic data, wood t...
C Brischke, A O Rapp, M Hasan, R Despot
Sorption properties of wood impregnated with aqueous solution of boric acid and montan wax emulsion
2010 - IRG/WP 10-40492
Non-biocidal techniques for wood protection become more and more important, nowadays. One of the possible treatments is use of water repellents. In the present research influence of, one of the possible water repellent, the montan wax emulsion, on the moisturizing and the sorption characteristic of impregnated wood was investigated. To achieve a better protection against wood decay fungi, montan w...
B Lesar, M Humar
Determination of Equilibrium Moisture Content (EMC) of wood in the neighboring Countries of Iran
2011 - IRG/WP 10-40540
The mean value of annual temperature and relative humidity of 33 cities in Azerbaijan, Armenia, Turkmenistan, Afghanistan, Pakistan, Oman, United Arab Emirates, Bahrain, Qatar, Kuwait, Iraq and Turkey were determined using climatic data of the past 11 years.
The EMC values were calculated using the Hailwood-Horrobin sorption model and its annual fluctuation, together with Temperature and relati...
A A Enayati, H Z Hosseinabadi
Growth conditions for fungal decay in wooden constructions – practical experience versus literature
2011 - IRG/WP 11-10758
Data regarding moisture and temperature requirements of decay fungi found in literature have been compared to experience from observations in a large number of Norwegian buildings. A number of selected situations are discussed, among those exposure to high relative humidity, exposure to free water and decay in the supposedly adverse conditions on Svalbard. The moisture content in wood has to be at...
M Sand Sivertsen, J Mattsson
The influence of moisture content and wood pH variation on fungal melanin formation in wood substrates
2011 - IRG/WP 11-10759
Wood decay patterns are strongly influenced by the conditions of the wood substrate, including moisture content and pH. In an antagonistic environment some fungi respond with pigment formation that helps to isolate and protect their mycelium. This is often associated with slower fungal growth and delay of wood mass loss. Dark colored melanin is the most common pigment formed by wood decay fungi, a...
D Tudor, S C Robinson, P A Cooper
Moisture protection and performance during 5 years exposure of 19 wood coating systems on a cladding in Vienna
2011 - IRG/WP 11-40561
A cladding with vertical boards of Norway spruce (Picea abies) comprising different coating systems had been exposed to natural weathering oriented south west in Vienna for 5 years. Weathering behaviour of the boards was assessed in intervals and wood moisture content was measured over the first 22 months of exposure. The moisture protective properties of the coating systems were assessed using la...
G Grüll, I Spitaler, M Truskaller
Performance of wood treated with linseed and tung oil against wood decay fungi and wetting
2012 - IRG/WP 12-30598
Most of the European wood species does not have durable wood. In order to use it in outdoor conditions nondurable material has to be protected. Nowadays, non-biocidal solutions for wood protection are attracting a lot of attention, particularly in use class 2 and 3 applications. One of the non-biocidal techniques is treatment of wood with water repellents like wax emulsions and oils. Linseed oil a...
M Humar, B Lesar
Relationships between heat treatment intensity and some conferred properties of different European softwood and hardwood species
2012 - IRG/WP 12-40593
Effect of treatment intensity on conferred properties like elemental composition, durability, anti swelling efficiency (ASE) and equilibrium moisture content (EMC) of different European softwood and hardwood species subjected to mild pyrolysis at 230°C under nitrogen for different durations has been investigated. Independently of the wood species studied, elemental composition is strongly correl...
M Chaouch, S Dumarçay, A Pétrissans, M Pétrissans, P Gérardin
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
Modern Instrumental Methods to Investigate the Mechanism of Biological Decay in Wood Plastic Composites
2014 - IRG/WP 14-40674
Various instrumental techniques were used to study the fungal decay process in wood plastic composite (WPC) boards. Commercial boards exposed near Hilo, Hawaii (HI) for eight years in both sun and shadow locations were inspected and tested periodically. After eight years of exposure, both boards were evaluated using magnetic resonance imaging (MRI), while a selected area of the board exposed in sh...
G Sun, R Ibach, M Gnatowski, J Glaeser, M Leung, J Haight
Experiences with an industrial system for controlled thermal wood modification in pressurized unsaturated steam
2014 - IRG/WP 14-40678
Thermal wood modification in pressurized reactors has a long history, but these processes are to date industrially scarcely used, because of the relatively complicated process equipment, compared to the more common high-temperature processes in kilns at atmospheric pressure. However, based on our practical experience with the FirmoLin® process, supported by recent scientific findings, it is foun...
W Willems
Interpretation of moisture monitoring data - Relevance of moisture content thresholds for fungal decay
2015 - IRG/WP 15-10839
It is widely accepted that besides temperature wood moisture content (MC) is the key factor when it comes to durability of wooden structures exposed to weathering. Many approaches to predict the service life of wooden structures have therefore been based on using wood MC as one major input-variable to develop dose-response relationships between material climate and decay response. However, to impr...
L Meyer, C Brischke
Introduction of the COST FP 1303 Cooperative Performance Test
2015 - IRG/WP 15-20567
COST Action FP 1303 “Performance of bio-based building materials” successfully started in October 2013 and an ambitious program was set up for the four year programme. COST Actions provide an excellent opportunity for collaborative research, e.g. in the frame of Round Robin tests. The idea of this respective test was to distribute a fairly simple test set up to as many places in Europe as poss...
M Humar, C Brischke, L Meyer, B Lesar, N Thaler, D Jones, S Bardage, C Belloncle, J Van den Bulcke, J M Abascal, G Alfredsen, D Baisch, B Brunnhuber, G Cofta, E Grodås, E Frühwald Hansson, M Irle, H Kallakas, J Kers, M Klamer, P Larsson Brelid, A B Maider, K C Mahnert, E Melcher, R Möller, M Noël, L Nunes, G A Ormondroyd, S Palanti, N Pfabigan, A Pilgård, A O Rapp, P Schumacher, E Suttie, T Teppand, M Touza, J Van Acker
Mould growth on spruce claddings and the effect of selected influencing factors after 4 years of outdoor testing
2015 - IRG/WP 15-30671
Norway spruce (Picea abies) is the most frequently chosen wood species as claddings in façades in Norway, and is used both coated and uncoated. The visual changes that occur during weathering can be colour changes, abrasion or wear, blistering, flaking, and even cracks in the wood or coating, but more often growth of mould and blue stain fungi is the main challenge. A field test with synchronous monitoring of relative humidity, air temperature, material temperature and wood moisture content in Norway spruce claddings has been performed in southern Norway as part of the ClimateLife project. Visual evaluation of blue stain and mould growth according to EN 927-3 was performed, and evaluation data after 46 months exposure is presented. The objectives were to study the effect of 1) environment, 2) cardinal direction and 3) colour of the coated surface on growth of blue stain and mould fungi and to study the variation in relative humidity, air temperature, wood moisture content and material temperature. After 46 months exposure, the red coating system had generally the lowest mould ratings and the uncoated claddings had the highest. Of the white coloured claddings the ones facing south had lower mould ratings than those facing north, but the opposite were found for red coloured claddings. The relative humidity was higher in front of claddings exposed northwards and in a shaded environment compared to an open environment against south. In an open environment red coloured claddings had the lowest wood moisture content and highest material temperature, and red coloured claddings against south had the highest maximum material temperature.
L Ross Gobakken, G I Vestøl
Superhydrophobic treatment of Norway spruce wood for improvement of its resistance against brown rot and moulds
2016 - IRG/WP 16-40734
Water repellence of wood can be increased and its some other properties influenced by introduction of hydrophobic chemicals into and on cell walls without affecting the wood’s bulk density due to lumen filling. Herein, a simple dipping method to insert octadecyltrichlorosilane (OTS) into cell walls and to deposit the self-assembled hydrophobic monolayers (SAMs) of OTS is reported. It was found o...
A Kumar, P Ryparová, P Hajek, B Kričej, M Pavlič, A S Škapin, M Šernek, J Tywoniak, J Žigon, M Petrič
Role of cell wall specific moisture content on the brown-rot fungal attack on wood
2016 - IRG/WP 16-40736
Wood is a hydroscopic resource because the cell wall polymers contain hydroxyl and other oxygen-containing groups that attract moisture through hydrogen bonding. Moisture content varies with changing moisture content in its environment. The moisture content in wood is responsible for many of the performance properties we observe. The strength properties of wood are dependent on the moisture con...
R M Rowell
Case study: “Riesenbühlturm”
2017 - IRG/WP 17-20599
In this case study four 7 m long Douglas fir crossbeams were investigated regarding the remaining metal and moisture content. The crossbeams were replaced from a timber tower after 10 years of service in the Black Forest region (South Germany) due to fungal decay. From each of the crossbeams five stem discs were taken and relevant parameters (density, moisture and remaining metal content) were de...
E Melcher, J Müller
The sorption behaviour of wood
2017 - IRG/WP 17-20605
The use of dynamic vapour sorption to determine the sorption properties of wood has become an increasingly popular technique. The method has many advantages when compared with many other gravimetric methods. However, it is necessary to set an equilibrium condition in order to obtain data for an isotherm in a reasonable amount of time. An important recent finding has been that multiple sorption cyc...
C Hill
COST FP 1303 Cooperative Performance Test – Results after two years outdoor exposure
2017 - IRG/WP 17-20620
COST Action FP 1303 ‘Performance of Bio-Based Building Materials’ started in October 2013 and an ambitious program was set up for four years. Among this a collaborative field test was planned. The idea of the cooperative performance test was to distribute a fairly simple test set up to as many places in Europe as possible in order to collect performance data reflecting the full range of climat...
B Lesar, M Humar, C Brischke, L Meyer-Veltrup, D Jones, N Thaler, J M Abascal, G Alfredsen, B Brunnhuber, E Grodås, M Irle, J Kers, M Klamer, K-C Mahnert, E Melcher, S Palanti, M Noël, E Suttie, N Pfabigan, M Touza
Moisture performance of wood determined in laboratory and field trials
2017 - IRG/WP 17-20621
It is widely accepted that wood moisture content (MC) is the key factor when it comes to durability of wooden structures exposed to weathering. The moisture performance of wood and wood-based products has been recognized as key element in wood durability and wood protection. Actually, it should be considered as major component of the material-intrinsic resistance of wood, but never found its way i...
D Kržišnik, N Thaler, B Lesar, M Humar
Impact of water holding capacity and moisture content of soil substrates on the moisture content of wood in terrestrial microcosms
2019 - IRG/WP 19-20662
Terrestrial microcosms (TMC) are frequently used for testing the durability of wood and wood-based materials as well as the protective effectiveness of wood preservatives. In contrary to experiments in soil ecology sciences, the experimental set-up is usually rather simple. However, for service life prediction of wood exposed in ground, it is of immanent interest to better understand the different...
C Brischke, F L Wegener
Monitoring of the building made of CLT in Ljubljana
2019 - IRG/WP 19-40860
Wood is one of the most important construction materials and its use in building applications has further expanded in recent decades, predominately due to development of the modern composites, like cross-laminated timber. In order to enable even more extensive and reliable use of wood in outdoor applications, factors affecting wood’s service life need to be understood. It is well known that fung...
M Humar, D Krzisnik, B Lesar, N Thaler, B Dujic
Moisture performance of wooden shingles tested on the Golobar cable yarding
2023 - IRG/WP 23-20704
Wood is a traditional roofing material in Europe and other parts of the world. In the 17th century, wooden roofing was generally used on more important buildings, but today it is mainly used on huts and houses in the Alpine regions. As wooden roofing is expensive, we investigated the possibility of extending the service life of the roofing through material selection and details. The roof of the Go...
M Humar, B Lesar, D Kržišnik