Your search resulted in 403 documents. Displaying 25 entries per page.
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
High-frequency monitoring of mass loss due to brown rot degradation of modified wood
2016 - IRG/WP 16-10862
Fungi growing in liquid culture undergoes three separate phases in which they i) adapt to the new environment, ii) grow unrestrictedly and exponentially, and iii) are inhibited to increase in number/mass due to lack of nutrients etc. Filamentous fungi have been shown to exhibit similar growth phases in a solid food substrate and have been modelled to grow in this way also in solid wood. In modifie...
R Ringman, A Pilgård, K Richter
On the effect of climate and exposure conditions on durability indicators and their potential for service life prediction of wood-based products
2016 - IRG/WP 16-20576
In order to encourage increased use of wood, different user groups need to be better informed regarding the variation in performance between different wood materials and the effect of different use classes. It is also important to provide good empirical data on the service life of wood products as input to for example life cycle assessment studies. In the current study the effect of temperature an...
G Alfredsen, C Brischke, P-O Flæte, M Humar, L Meyer-Veltrup
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
Measurement of Cell Wall Moisture in Acetylated Radiata Pine Using Low-Field Nuclear Magnetic Resonance
2016 - IRG/WP 16-20583
Understanding the interaction of water with acetylated wood is necessary to explain how the protective mechanism of acetylation functions. Low-field nuclear magnetic resonance is one technique for assessing water in wood. Pinus radiata earlywood sapwood samples were acetylated to various weight percentage gains and then analysed with this method. Increased levels of acetylation showed significantl...
H G Beck, C A S Hill
Durability of a willow/plastic composite mat
2016 - IRG/WP 16-20592
Developing uses for wood wastes could enhance utilization of low value renewable materials while creating opportunities for rural development. Small diameter willow stems have little use in China, but they could be combined with high density polyethylene to create wood plastic composite mats for decorative applications. These mats could be used in exterior, above ground exposures, but would still ...
Li Yan, Haiyan Duan, Beizhan Quan, J Cappellazzi, J J Morrell
Distribution and penetration of the tung oil in wood studied by high-resolution magnetic resonance imaging
2016 - IRG/WP 16-20593
Water repellents as environment-friendly treatments are gaining their popularity as non-biocidal solutions for wood protection. One of the most important water repellents for wood besides waxes and organosilicon compounds are drying oils. Tung oil is one of the best performing oil. However, tung oil, similarly as other oils, does not penetrate deeply into wood, due to its high viscosity. In order...
M Žlahtič, U Mikac, I Serša, M Merela, M Humar
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
Insight in moisture dynamics of wood treated with organosilicon compounds
2016 - IRG/WP 16-20598
The SILEX project “Improving sustainability of construction materials using innovative Silicon based treatment” is a Life+ project with reference LIFE+11 ENV/BE/1046 and started in April 2013. This project intends to demonstrate that a new class of compounds can be used for wood treatment for an extended service life combined with enhanced new testing methodology. The project aims at demonstra...
J Van Acker, J Van den Bulcke, I De Windt, S Colpaert, S De Rocker, S Salvati, J-P Lecomte
Termiticidal Effect of Bitumen and Creosote oil Treatments on Selected Nigerian Wood Species
2016 - IRG/WP 16-30689
Termites attack has been a major threat to wood materials in construction. The study investigated the termiticidal effect of bitumen and creosote oil mixture on the resistance of some commonly used indigenous wood species namely: Celtis zenkeri, Terminalia ivorensis, Albizia lebbeck, Cola gigantea and Terminalia superba to termites in Akure, Ondo State, Nigeria. The wood species were obtained from...
Termiticidal Effect of Bitumen and Creosote oil Treatments on Selected Nigerian Wood Species
The durability of manufactured structural building materials
2016 - IRG/WP 16-40718
The projected market potential for Engineered Wood Products such as CLT (cross laminated timber) is very positive however, potential prolonged rain leakage or moisture exposure during construction and in-service could pose considerable concern for its durability and reputation. This research was conducted to assess the decay resistance of CLT and OSB (oriented strand board) in an accelerated trial...
T Singh, D Page
Incorporation of raw boron minerals to protect particleboard against decay and mold fungi, termites and insects
2016 - IRG/WP 16-40729
This paper evaluated the biological performance of particleboards incorporated with the raw boron minerals ulexite and colemanite against decay, mold fungi, termites and insect larvae in comparison with that of particleboards with zinc borate, or boric acid plus a borax mixture. The results showed that ulexite and colemanite were highly effective against the decay fungi and termite attack in labor...
S N Kartal, E Terzi, P Gerardin, C M Ibanez, T Yoshimura
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
Encapsulation of poles to prevent moisture uptake – a laboratory test
2016 - IRG/WP 16-40753
Premature failure of utility poles due to decay in soil contact is the main reason for early removal of utility poles, a measure that implies extra costs for utilities. Remedial treatments and barriers are common methods to prolong the service life of utility poles. The first part of this paper gives an overview of mode of action and commercial application of barrier systems as described in the li...
K-C Mahnert, U Hundhausen
Development of Wood Modification – High melting point wax and hot oil treatments
2016 - IRG/WP 16-40768
This study covers an introduction to the projects where new facilities were created for developing wood modification. In this new research environment it is possible to treat wood with versatile equipment. First modifications with this equipment are going to be done in high temperature and pressure using high melting point waxes and hot oils.
Earlier studies, tests and commercial products show...
H Turunen, L Linkosalmi, J Peura, O Paajanen
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
Influence of Weathering on Moisture Performance of Wood
2017 - IRG/WP 17-20619
Water performance of wood is besides the inherent durability the most important factor that influences on the performance of wood in outdoor, above ground applications. Therefore it is of significant importance to optimize the methods that are able to predict the moisture behaviour of wood in outdoor applications. In order to elucidate this questions, samples were prepared of oak (Quercus), sweet ...
M Žlahtič-Zupanc, B Lesar, N Thaler, M Humar
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