Your search resulted in 388 documents. Displaying 25 entries per page.
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
The influence of microclimate on the moisture conditions in a Norway spruce (Picea abies (L.) Karst.) joint exposed to artificial rain
2013 - IRG/WP 13-20505
Wood structures outdoors are susceptible to decay if they are exposed to high moisture contents during long periods of time. Structures with joints that act as water traps are especially exposed since high moisture contents are reached in such positions. This paper presents a part of a laboratory study that concerns the relationship between the microclimate and the material climate, i.e. the moist...
M Fredriksson, L Wadsö, P Johansson
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
Climatic impacts on the moisture performance of wooden decking and facades
2013 - IRG/WP 13-20518
In outdoor usage wood is exposed to a variety of influences, which reduce its durability against biological deterioration and wetting. Besides many other factors the service life of wooden facades and cladding is dominated by occurring moisture loads on the one hand and their capability to withstand moisture on the other hand. Hence, climatic factors have a direct impact on the material climate an...
T Bornemann, C Brischke, G Alfredsen
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
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
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
Non-destructive monitoring of structure and moisture dynamics of plywood exposed outdoors to improve service life prediction and fit-for-purpose design
2015 - IRG/WP 15-20570
Plywood is an important construction material yet prone to water uptake, which can decrease strength and increase decay risk. To predict service life and improve fit-for-purpose design, it is crucial to understand the moisture behavior and structural changes of plywood. In this research, several plywood specimens were exposed outdoors for approximately one year. During this period, the moisture di...
W Li, J Van den Bulcke, I De Windt, M Dierick, 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
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
Bundle tests - Simple alternatives to standard above ground field test methods
2016 - IRG/WP 16-20581
Within this study we applied different new above ground test set ups to untreated Norway spruce (Picea abies Karst.) and Scots pine sapwood (Pinus sylvestris L.) which are frequently used as reference or control species in wood durability field tests. The overall aim of this study was to find a simple alternative method to the few standardized above ground field test methods, such as the L-joint a...
C Brischke, L Meyer-Veltrup
Moisture monitoring in WW2 partisan hospital Franja
2016 - IRG/WP 16-20596
Material climate of wood used for construction of WW2 Partisan hospital Franja was monitored for approximately one year. Partisan hospital is located in the bottom of tiny gorge Pasice in Slovenia. Hence, wood moisture content on eight respective location and wood temperature was determined twice per day with Scanntronik equipment Gigamodul and Thermofox. The results clearly showed that despite of...
M Humar, N Thaler, B Lesar, A Žagar
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
Modelling of moisture content in timber bridge details
2017 - IRG/WP 17-20613
The design of details is an important aspect in durability design of timber bridges. Details are often considered the weakest points in bridges due to their tendency to trap and accumulate moisture and thus facilitate decay. When designing maintenance plans and inspection intervals, it is important to know how design choices will come to influence the service life. Moreover, service life and wood ...
J Niklewski, C Brischke, E Frühwald Hansson, L Meyer-Veltrup
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
Moisture content as a quality control parameter in thermally modified timber production
2017 - IRG/WP 17-20622
Quality assurance (QA) or factory production control (FPC) is necessary to ensure a proper production process. The requirements of QA/FPC can result from EN and national standards, quality assurance systems, or producer-specific rules.
TMT producers must ensure that the process was correct, and to ensure traceability of products. In addition to the electronic records, the material should be che...
W Scheiding, H Turkulin, S Stein
Exploring the use of X-ray micro CT as a tool for the monitoring of moisture production and mass loss during lab-based fungal degradation testing
2019 - IRG/WP 19-20654
Bio-based building materials, such as wood and wood-engineered products, are susceptible to degradation by decay fungi. In-depth knowledge on the intricate material-fungus relationship as well as performance data for many bio-based building materials are still lacking, and especially knowledge on how a material’s structure and moisture properties affect the degradation process is missing. Althou...
L De Ligne, J Van den Bulcke, A De Muynck, J M Baetens, B De Baets, L Van Hoorebeke, J Van Acker
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