Your search resulted in 1022 documents. Displaying 25 entries per page.
The effect of preservative treatment on mechanical strength and structural integrity of wood
2015 - IRG/WP 15-30667
The use of wood for demanding construction applications is increasing in Europe. Wooden constructions are frequently designed of susceptible conifer wood, which is endangered by wood decay fungi in wet applications. Therefore in many cases treating wood with preservatives is unavoidable to ensure the desired service life. However, chemical treatment of wood can result in changes of its mechanical ...
M Humar, D Kržišnik, C Brischke
Durability of Fence Posts of Four Wood Species After 20 Years in Field Test
2015 - IRG/WP 15-30670
In the past years, wood consumption from native forests has drastically reduced the availability of wood. Fast-growing species such as Pinus and Eucalyptus suitably impregnated with chemicals may show a service life equal or higher than hardwood with high natural durability. The field tests have been an alternative widely used to evaluate the durability of wood and the efficiency of preservatives....
A Florian da Costa, A C Salgado de Freitas, E Meneses Oliveira
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
Some comments on durability testing of WPC according to EN 15534-1
2015 - IRG/WP 15-40695
The standard EN 15534-1 (2014) gives advice for broad characterization of WPC materials and products. It contains instructions for test procedures concerning different properties e.g. mechanical properties, thermal properties, as well as durability.
In this paper some WPC materials from the market were tested for their resistance against brown rot. Furthermore, the water uptake and bending prope...
S Bollmus, A Gellerich, H Militz
How does the test methodology influence the outcome of durability testing of thermally modified wood
2015 - IRG/WP 15-40699
Thermally modified wood is commercially available on the European market since many years. Today, many production units with various production capacities and different modification processes exist. Industrial scale wood heat treatment processes, under the trade name of ThermoWood were developed in Finland. ThermoWood has two standard treatment classes with different target properties, namely Ther...
A Gellerich, S Bollmus, H Militz
Investigation of Dimensional Stability and Coating Performance of Different Heat-Treated Poplar Wood Before and After Accelerated Aging
2015 - IRG/WP 15-40702
In this investigation, coating performance of heat-treated poplar wood (Populus tremuloioes) in different environments, before and after accelerated aging was studied. Specimens with 150×100×20 mm and 20×20×20 mm in dimensions were prepared. Heat treatments were performed in air, steam and linseed oil media. Specimens were coated by alkyd based stain. Adhesion strength before and after aging, ...
A Talaei, D Ansari Movahed, G Rassam
Termite and insect resistance of acetylated wood
2015 - IRG/WP 15-40703
The benefits from acetylation of wood to enhance resistance against fungal decay and dimensional stability have been known for many years. Since 2007 Accsys Technologies has been commercially producing Accoya® wood that is based on acetylation of radiata pine. A number of studies on the resistance of acetylated wood to attack by wood destroying termites have been conducted, but there is no common...
F Bongers, M Kutnik, I Paulmier, J Alexander, H Militz
Experimental Measurements of Fire Retardants on Plywood at Fire Test
2015 - IRG/WP 15-40709
The use and development of wood composite materials increased in the past few years. However, in Brazil there are some restrictions on these products regarding their use, since it could be considered a potential risk at a fire situation. Thus, becomes evident the need for researches aiming to fit these in safety standards. This study aims to evaluate the efficiency of two new fire retardant produc...
G C A Martins, L A Marcolin, J M Vidal, C Calil Jr
Steam accelerated borate diffusion: Optimizing dry tie treatment
2015 - IRG/WP 15-40713
A small laboratory study was carried out which demonstrated that dry wood dip treated in a high concentration borate solution could not be subsequently treated properly with oil borne copper naphthenate unless it was subsequently steam treated to accelerate borate penetration into the wood and re-dry the wood beforehand. A larger study with commercial sized cross ties (railway sleepers) was carri...
J-W Kim, J D Lloyd
Shells of Coconut and their Durability against Termite Attack
2015 - IRG 15-10853
All tropical and subtropical areas of the Earth are inhabited by termites. In climates with moderate temperatures, they occur less frequently. Especially wood and non-wood materials that grows in tropical areas and used there in timber constructions and woodworking, wood durability and protection against termites should be researched. This paper reports findings from an experimental “AW011” la...
M Dass, A H H Wong, W Unger
Foundation piles: analysis of beech wood decay in service life conditions
2016 - IRG/WP 16-10858
Wood piles foundation system was largely used over decades. Thus, numerous buildings over the world are based on this constructive system. In the context of reduction of CO2 emissions in the building field of constructions, substitution of concrete by wood as material for foundation piles seems to be a promising alternative. However, fluctuation of the water table level in soil may promote fungal ...
Q Kleindienst, A Besserer, M-L Antoine, C Perrin, J-F Bocquet, L Bléron
Production of reactive oxygen species in the presence of oxidized iron and oxalate under conditions mimicking brown-rot fungal degradation of wood
2016 - IRG/WP 16-10861
The biochemical role of oxalate in the fungal solubilization of iron is well known, but additional information is needed on the role that oxalate plays in the brown-rot decay of lignocellulose. In this study iron sequestration from iron and iron oxide-hydroxides was assessed with regard to the function of a chelator-mediated Fenton (CMF) reaction and the generation of reactive oxygen species (ROS)...
Yuan Zhu, Liangpeng Zhuang, B Goodell, Jinzhen Cao, J Mahaney
Fungal decay of archaeological waterlogged oak timber: role of the mineral content
2016 - IRG/WP 16-10873
In service, wood foundation poles are subjected to water level fluctuation in soil. While wood is saturated by water only bacterial decay occurs. When oxygen content increases and moisture content decreases, severe fungal attack may occur. To evaluate the long term fungal durability of wood foundation pole in the context of service, 300 years waterlogged archaeological wood poles were used. The oa...
A Besserer, M Letellier, E Fredon, Q Kleindienst, M-L Antoine, C Perrin, J Lallemand, C Rose, M-C Trouy
Selection of most aggressive test fungi for modified wood - Practical laboratory experience
2016 - IRG/WP 16-20579
One main objective of wood modification processes is the improvement of the durability against wood destroying organisms. Therefore, investigations of the resistance against wood destroying fungi have been one of the main focus within the last years. For the interpretation of the durability results, the selection of suitable test fungi is one of the main questions. A “wrong” fungus species may...
A Gellerich, S Bollmus
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
Studying fungal growth using automated image analysis and computer simulations
2016 - IRG/WP 16-20590
Wooden materials are prone to fungal attack resulting in damage and economic losses. Therefore many efforts have been made to understand the degradation of wood and to avoid the adverse effect of fungi. Even though the extent of degradation of a material is inversely proportional to the extension of the fungi attacking it, most researchers focus mainly on the former, leaving the study of the latte...
G Vidal-Diez de Ulzurrun, J M Baetens, J Van den Bulcke, B De Baets
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
Effects of fungal exposure on air and liquid permeability of nanosilver- and nanozincoxide-impregnated Paulownia wood
2016 - IRG/WP 16-30680
Effects of aqueous dispersion of silver and zinc-oxide nano-particles on air and liquid permeability of Paulownia wood exposed to T. versicolor were studied in the present research project. Specimens were also heat-treated at 100 and 150°C and compared with the control specimens. Permeability values were measured when the moisture content of the specimens was 12%. Results showed significant incre...
H R Taghiyari, A Kalantari, M Ghorbani Kookandeh, F Bavaneghi, M Akhtari
Accelerated Weathering Performance of Impregnated Wood Samples Coated with Zinc by Means of Plasma-Assisted Particle Deposition
2016 - IRG/WP 16-30682
Many different methods are currently applied for wood protection against outdoor conditions. The most important of these is the process of impregnation with liquid substances. However, this kind of wood preservatives cannot provide a long-term protection of wooden surfaces. Weathering-resistant surfaces can be obtained by applying UV absorbing agents. In this study, the influence of zinc particles...
A Can, H Sivrikaya
Laboratory and Field evaluation on Resistance of Thiacloprid-treated Pine Species to Termites in Mexico
2016 - IRG/WP 16-30687
The usage of Neonicotinoids for wood preservatives is common practice in several countries. Especially the active ingredient Imidacloprid is well established for this application due to its high efficacy against termites. (2Z)-3-(6-chloro-3-pyridylmethyl)-1,3-thiazolidin-2-ylidene-cyanamide, also known as Thiacloprid showed a good efficacy against Reticulitermes santonensis De Feytaud in efficacy ...
P Meckler, T Jaetsch, I Rodriguez
Activity of wood preservatives against mould fungi
2016 - IRG/WP 16-30695
The resistance of experimental and commercial wood preservatives to mould fungi was determined using a method recommended by the Building Research Institute Instruction. The research of the inhibiting actions of the growth of fungi was carried out on the Scots pine wood Pinus sylvestris L. and beech Fagus sylvatica L. The most active compounds against mould were experimental herbicidal ionic li...
J Zabielska-Matejuk, A Stangierska
Resistance of heat treated Ash wood under steam pressure: rot fungi, soil micro-organisms and termites
2016 - IRG/WP 16-40724
Thermal modification processes have been developed to increase the biological durability and dimensional stability of wood. The aim of this paper was to study the influence of ThermoWood® treatment intensity on wood decay resistance improvement against soil-inhabiting micro-organisms, brown/white rots and termite’s exposures. All of the tests were carried out in the laboratory with two differen...
K Candelier, S Hannouz, M-F Thévenon, D Guibal, P Gérardin, M Pétrissans, R Collet
The durability of natural and thermomodified black poplar wood and Scots pine sapwood after two years of external exposition
2016 - IRG/WP 16-40730
Natural biological durability of many European wood species is considered to be relatively small, particularly in a ground contact conditions. This is due to the exposure of the wood to the range of biological and atmospheric destructive factors. This may to limit the scope of application of the wood of these species, particularly in construction. The biocides are often used for wood protection in...
A Fojutowski, A Kropacz, A Noskowiak
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