Your search resulted in 340 documents. Displaying 25 entries per page.
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
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
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
Modelling the risk for mould growth on timber stored outdoors protected from rain
2013 - IRG/WP 13-20529
A mould resistance design (MRD) model was used to calculate the maximum duration of storage of timber outdoors under cover (protected from rain) before the onset of mould growth on the surface of wood. The prediction model is based on laboratory tests performed in constant and cyclic climates and were also confirmed against exposure tests in attics and crawl spaces. The prediction model presented ...
E Frühwald Hansson, S Bardage, S Thelandersson
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
Critical moisture levels and mould resistance of five different wood treatments
2013 - IRG/WP 13-30632
Mould resistance of five different treatments were tested using two methods, a recently
developed method for the determination of critical moisture levels of building materials (RHcrit),
and ASTM D3273-94. The critical moisture level method exposed samples at 22 °C and 98, 92,
86 and 82% relative humidity (RH) for 12 weeks. ASTM D3273-94 was performed at 29 °C and
about 95% RH.
Treatments c...
G Bok, P Johansson, A Ekstrand Tobin, S Bardage
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
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
Moisture dynamics of wood and wood-based products – Results from an inter-laboratory test
2014 - IRG/WP 14-20539
In the frame of the European research project PerformWOOD in close liaison with the CEN task group TG EN 350 of CEN TC 38 WG 21 in total six research institutes teamed up and initiated an inter-lab trial (Round Robin) to investigate the suitability of different test methods to determine the wetting ability of wood. The moisture performance of wood and wood-based products has been recognized as key...
C Brischke, L Meyer, C Hesse, J Van Acker, I De Windt, J Van den Bulcke, E Conti, M Humar, H Viitanen, M Kutnik, L Malassenet
Communities of mold fungi in moisture damaged building materials
2014 - IRG/WP 14-20542
The critical conditions needed for the development of mould and decay fungi have been modelled for different building materials. However, current knowledge of indoor microbes growing on building materials relies on culture-based methods and more advanced molecular biological techniques should be employed to study the complex microbial communities in building materials. In this paper molecular biol...
E Sohlberg, H Viitanen
A screening of factors that might influence the result of laboratory decay tests
2014 - IRG/WP 14-20548
Laboratory fungal decay tests provide important tools for performance testing of wood materials. But they are also hampered with some uncertainties regarding reproducibility. In addition to variation between fungal species and strains the test conditions are also believed to have some influence. The aim of this study was to screen the effect of a selection of test parameters that might influence t...
E Larnøy, G Alfredsen, A Treu, S Kolstad
Changes in mechanical and chemical properties of wood exposed outdoors
2014 - IRG/WP 14-20550
The aim of this study was to investigate differences in certain mechanical and chemical properties of three different wood species (common beach (Fagus sylvatica), Norway spruce (Picea abies), and copper-ethanolamine (CuE) impregnated Norway spruce (Picea abies)) that were exposed in use class 3 (CEN, 2006) for periods between 4 and 30 months. The results show, that changes in the investigated me...
N Thaler, C Brischke, D Žlindra, V Vek, M Humar
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
Biological durability of natural fibre reinforced composites
2014 - IRG/WP 14-40681
Composite materials reinforced with wood or non-wood natural fibres have the potential to be a lighter and lower-cost alternative construction material. Until better availability and properties and a lower cost price of degradable polymers makes their use more prevalent, the application of natural fibre reinforcements in synthetic polymers is an intermediate step towards products that are complete...
N Defoirdt, I De Windt, J Van den Bulcke, J Van Acker
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
Remote sensing for detection of termite infestations—Proof of Concept
2015 - IRG/WP 15-10846
This paper reports the results of a search to discover the most cost effective and robust method of detecting Reticulitermes flavipes infestations in structural members of remote bridges, homes and other wooden structures and transmitting these results to internet cloud storage thus obviating routine travel to these structures for periodic visual inspections. Duplicate stainless steel tanks were c...
F Green III, R A Arango, C R Boardman, K J Bourne, J C Hermanson, R A Munson
Acceptance levels of surface disfigurement - tolerance to defects of coated wood
2015 - IRG/WP 15-20564
Service life planning (PSL) has become an important issue in performance based building and substantial progress has been made in recent years. The role of predicting the aesthetical service life of wooden building components has been underestimated for quite long time but is recently attracting more and more notice. It is influenced by numerous factors such as discoloration, fading, flaking, crac...
C Brischke, P Kaudewitz
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
A review of the analytical methods used in determining the decay resistance of heat treated wood
2015 - IRG/WP 15-40690
Heat treatment as a wood process is increasingly used because of its non-biocide behaviour and its low environmental impact. This sort of treatment is based on biopolymer chemical degradation by heat transfer. This process improves mainly the dimensional stability and the decay resistance of wood.
Wood becomes darker after this type of treatment and thus gives it an aesthetic appearance. These i...
K Candelier, M-F Thévenon, A Pétrissans, S Dumarçay, P Gérardin, M Pétrissans
Global survey on durability variation – on the effect of the reference species
2016 - IRG/WP 16-20573
Climate change due to anthropogenic emissions is the largest environmental challenge of our time. Forest-based value chains play an important role in reducing the accumulation of CO2 in the atmosphere. Maximizing the use of wood to tackle climate change requires improved understanding of the service life of timber products. This information can best be obtained from field testing and while there i...
R Stirling, G Alfredsen, C Brischke, I De Windt, L P Francis, E Frühwald Hansson, M Humar, J Jermer, M Klamer, M Kutnik, P Laks, I Le Bayon, S Metsä-Kortelainen, L Meyer-Veltrup, P I Morris, J Norton, T Singh, J Van Acker, J Van den Bulcke, T M Venås, H Viitanen, A H H Wong
Moisture induced risk and fungal development in various field test set-ups in and above ground
2016 - IRG/WP 16-20577
A high number of studies on the decay performance of wood in outdoor exposure have been conducted in the past. However, no testing methodology for wooden components exposed above ground reflecting the variety of different loads has been established so far. Many test protocols were modified in different ways throughout the years and results were often published in an encoded or incomplete way. This...
L Meyer-Veltrup, C Brischke
Variation in moisture content in field trials according to use class 3.2 conditions
2016 - IRG/WP 16-20580
Different test methods to determine the durability of wood in use class 3 (EN 335:2013) are available. Fungal degradation of wood requires liquid water. Different Standards (EN 335-1:2006; DIN 68 800:2011) specify the risk for decay with moisture content (mc) of above 20%. EN 335 (2013) does not specify moisture content but rather defined limited wetting conditions (use class 3.1) or prolonged wet...
S Bollmus, A Gellerich, H Militz
Modelling the performance of bio-based building materials
2016 - IRG/WP 16-20582
The ‘bio-based economy’ represents a growing area of development globally and covers a wide range of building materials including wood and wood-based products. A ‘bio-based’ material is intentionally made from substances derived from living (or once-living) organisms. In this context it means that the materials and products are made from renewable resources, with the criteria that a renewa...
C Brischke