Your search resulted in 372 documents. Displaying 25 entries per page.
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
Improving our understanding of moisture and other durability-related properties of wood in building envelope performance prediction
2011 - IRG/WP 11-20468
Building science has become an increasingly important field in recent years with rapid changes in construction methods, building materials and consumer expectations. The field has also been brought to prominence by a few large-scale premature building envelope failures in a few regions across the world. Considerable effort has been put into developing hygrothermal models to simulate heat, air, vap...
Jieying Wang, P Morris
Decay initiation in plywood, OSB and solid wood under marginal moisture conditions
2011 - IRG/WP 11-20469
Hygrothermal models are increasingly used as research tools by building scientists and and design tools by designers to simulate heat, air, vapour, and water movements within and through building envelope and even to predict the consequences in terms of mould/decay growth and metal corrosion. This work was designed to generate data on decay initiation under marginal moisture conditions to support...
Jieying Wang, P Morris
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
Long term durability of the heartwood of seven common softwood species in above ground conditions
2012 - IRG/WP 12-10771
The natural durability for wood in above ground use has been evaluated based on results after 11 years of exposure in a test site situated at the Danish Technological Institute in Taastrup, Denmark. Selected results for seven common softwood species exposed horizontally are reported. The test results cover samples with direct rain exposure (use class 3 of the European standard EN335-1:2006) and sa...
E Tang Engelund, M Klamer, T Mark Venås, B Lindegaard
Influence of soil moisture, Sarawak soil types and decay types on decay susceptibility of rubberwood and kelempayan
2012 - IRG/WP 12-10780
Wood and soils are important natural resources of the land, the former widely used as structural supports in contact with the latter. Many low durability wood species exposed to soil contact has reportedly high incidence of decay failures in poorly treated and untreated materials depending on soil types, properties and soil microbial virulence. This paper probes the relationship of the main soil t...
A H.H. Wong, P K.F. Chong, J Sabang
Plywood under the scanner: linking moisture dynamics and 3D structure
2012 - IRG/WP 12-20491
Plywood is highly esteemed as a construction material. Yet, the influence of moisture on both strength and durability are important factors. Especially the dynamics of moisture desorption and absorption should be taken into account when assessing the quality of a panel, which is a fact for all panel materials. This paper therefore focuses on the monitoring of the moisture dynamics of plywood subje...
J Van den Bulcke, I De Windt, N Defoirdt, J Van Acker
Comparative studies on the moisture performance and durability of wooden facades
2012 - IRG/WP 12-20492
Wooden claddings are traditionally used in many parts of the world. Also modern structures are frequently made from timber and timber engineering panel products. However, wood has to compete with other cladding materials and its durability needs to assure sufficient functional and aesthetic service life. Besides many other factors the durability of a wooden facade is dominated by its moisture perf...
T Bornemann, C Brischke, J-M Lück
Moisture performance based wood durability testing
2012 - IRG/WP 12-20495
In the frame of a scientific cooperation within the Swedish research program ‘WoodBuild’ comparative field and laboratory durability studies have been carried out by the Technical Research Institute of Sweden SP and Leibniz University Hannover. One objective was to improve test methods as well as evaluation systems in order to facilitate the use of (field) testing for service life prediction. ...
L Meyer, C Brischke, A Pilgård
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
Effect of preservative treatment on dimensional stability of plywood made of treated simul (Bombax ceiba) veneer
2012 - IRG/WP 12-40575
The dimensional stability such as thickness swelling and water absorption of plywood made of treated simul (Bombax ceiba) veneers were investigated after 2 hours and 24 hours soaking under water. The veneers were treated with hot water and cold water solution of borax-boric acid (1:1), neem leaves and mahogany seeds of different concentration (1:10, 1:20, and 1:40) at different treatment duration....
K Akhter, M Mahabubur Rahaman, A Ara
The effect of press time on springback and water absorption of acetylated particleboard
2012 - IRG/WP 12-40579
In this study the effect of press time on springback, thickness swelling and water absorption was investigated. After 24 hours soaking in acetic anhydride, in order to achieving WPG 17%, acetylated particles were heated in an oven at 120 0C for 360 minutes. Acetylated and nonacetylated (control) particleboards were produced with 10% melamine urea formaldehyde (based on the oven-dry weight of part...
F Bavaneghi, M Ghorbani, A Kargarfard
Water uptake of wood surfaces with and without coating: influence of weathering
2012 - IRG/WP 12-40580
The objective of this study was to compare liquid water absorption of wood surfaces with and without coating, before and after artificial weathering. Samples of spruce, oak and sapelli were exposed to the EN 927-6 cycle for 1500 and 1850 hours and to the weathering produced by the Garner wheel for 1000 hours. Two highly pigmented coatings (solventborne and waterborne) and two semi-transparent stai...
L Podgorski, S Collignan, J D Lanvin
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
Effects of nano-wollastonite impregnation on fire resistance and dimensional stability of Poplar wood
2012 - IRG/WP 12-40595
The fire-retardant properties of Nano-Wollastonite (NW) in poplar wood (Populus nigra) were determined in this study. Some physical properties such as water absorption, volumetric swelling and Anti-Swelling Efficiency (ASE) were also measured. Specimens were prepared according to the ISO 11925 standard for the fire-retarding properties, and ASTM D4446-2002 standard for the physical properties. Imp...
A Karimi, A Haghighi Poshtir, H Reza Taghiyari, Y Hamzeh, A Akbar Enayati
The effect of nanozycosil on the water absorption and dimensional stability of Beech wood
2012 - IRG/WP 12-40606
Zycosil is a clear penetrating water repellent. This product works by penetrating into the substrate and modifying the surface tension to inhibit water intrusion. Beech wood (Fagus orientalis) was modified by treatment with nanozycosil. Then water absorption and dimensional stability in terms of volumetric swelling percent and anti-swelling efficiency were determined and found to be improved on t...
M Ghorbani, F Bavaneghi
Field-testing of Norway Spruce Claddings with Monitoring of Moisture Content, Material Temperature and Microclimate
2012 - IRG/WP 12-20502
The physical function of a cladding is to protect the interior construction. Under normal circumstances the performance requirements can be met for a very long time, meaning that the technical service life of a wooden cladding can be very long. Since the cladding is a major part of the facade, it also has visual requirements that may define the aesthetic service life, and often it is much shorter ...
G I Vestøl, L Ross Gobakken
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
Protective nanoparticle coating reducing water absorption of wood species
2012 - IRG/WP 12-40614
Nanoparticle coatings were deposited onto different tropical wood samples for controlling the surface hydrophobicity. The styrene(maleimide) nanoparticles were synthesized in aqueous dispersions under pure conditions or in combination with 70 wt.-% palm oil. A first evaluation of the non-coated wood surfaces indicates a high dependence between the water contact angles, the average surface roughnes...
P Samyn, A Paredes, G Becker, H Van den Abbeele, L Vonck, D Stanssens
Water absorption and desorption of non treated, pressure impregnated, and pine oil treated glulam made of small diameter Scots pine and Norway spruce
2012 - IRG/WP 12-40616
A growing proportion of harvested timber originates from the first or second commercial thinning stands in Finland, which means smaller average log volumes in comparison to final felling stands. Smaller log volume means challenging wood properties such as higher proportion of juvenile wood and sapwood. Due to these facts, products made of small diameter logs are prone to twist and check, and have ...
H Heräjärvi, V Möttönen, R Stöd
Activities of moulds on wood as a function of relative humidity during desorption and absorption processes
2013 - IRG/WP 13-10794
Three different types of indoor moulds: Penicillium brevicompactum, primary colonizer; Alternaria tenuissima, secondary colonizer and Trichoderma harzianum, tertiary colonizer, grown on wood were measured for their activities under different relative humidity levels. The activities were measured by isothermal calorimetry. The activities of the moulds changed with the change of the relative humidit...
Yujing Li, L Wadsö
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