Your search resulted in 340 documents. Displaying 25 entries per page.
Methods of field data evaluation - time versus reliability
2011 - IRG/WP 11-20466
Field testing of wood and wood-based products is so far the most reliable way to get information on performance with respect to durability and expected service life. However, field trials are extremely time and cost consuming. The main objective of the present study was to investigate possible correlations between early stages of decay, preferably during the first 5 years, and the actual service l...
P Larsson Brelid, C Brischke, A O Rapp, M Hansson, M Westin, J Jermer, A Pilgård
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
Performances of Douglas fir in real outdoor use conditions
2011 - IRG/WP 11-20472
The European standard EN 350-2 classifies Douglas fir as moderately resistant to fungal decay on the basis of standardized laboratory and field tests. However, the lifespan expectancy of outdoor structures such as cladding, decking and elements of wood construction carpentry may also vary according to environmental conditions (climate, exposure to weathering), maintenance and design. An investigat...
M Kutnik, S Lepetit, S Le Nevé
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
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
Durability of timber products – Part 2: Proposal for an IRGWP - Durability Database
2012 - IRG/WP 12-20497
A proposal for a web-based platform for scientific exchange of test data in the field of wood durability and wood protection has been made. The overall aim of the durability data base is to improve the usability of existing test data and to create an added value for durability research and service life prediction.
The database allows for test results from standardized and non-standardized laborat...
C Brischke, L Meyer, G Alfredsen, M Humar, L Francis
Durability of timber products –Part 1: Inventory and evaluation of above ground data
2012 - IRG/WP12-20498
The material-inherent resistance of wood is one of the most important qualities influencing the durability of timber. Hence, it has also a major effect on the service life to be expected from a timber construction. In addition, design details and the respective climatic conditions determine durability and make it impossible to treat wood durability as an absolute value. Moreover, the reference mag...
C Brischke, L Meyer, G Alfredsen, M Humar, L Francis, P O Flæte, P Larsson Brelid
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
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
A survey of factors affecting decay resistance of wood modified with acetic anhydride
2012 - IRG/WP 12-40594
From the range of information published, acetylation appears well suited to provide adequate protection against biological attack for materials derived from typically non-durable wood species. Acetylated wood is now commercially available both in Europe and in the USA. But still there are a lot of unanswered questions related to fungal decay mechanisms in acetylated wood. The paper summarize exist...
G Alfredsen, P O Flæte, H Militz
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
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
Quasi-in-situ durability tests on oak timber bridges
2013 - IRG/WP 13-20510
This study aims on developing a method for determination of wood durability on samples taken from real structures in service. Therefore quasi-in-situ durability tests have been conducted exemplarily on timber bridges made from English oak (Quercus robur L.). Drilling cores were found to be a feasible alternative to standard specimens for laboratory durability tests against pure cultures of Basidio...
C Brischke, C J Behnen, M-T Lenz, K Brandt, E Melcher
Changes of fungicidal, mechanical and sorption properties of wood during above ground outdoor exposure
2013 - IRG/WP 13-20513
The aim of this preliminary study was to investigate differences in mechanical, fungicidal, and sorption properties of four different wood species (sweet chestnut (Castanea sativa), common beach (Fagus sylvatica), Norway spruce (Picea abies), and copper-ethanolamine (CuE) impregnated Norway spruce (Picea abies)) that were exposed in the 3rd use class (CEN, 1992) for periods between 4 and 30 months...
N Thaler, M Humar
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
Predicting the Rate of Decay, and the Potential for Misinterpretation of Proper Scientific Method
2013 - IRG/WP 13-20525
Predicting the rate of fungal attack in wood-based materials and its effect on properties remains the holy grail of wood products pathologists; however, achieving this goal is difficult because of the many variables associated with the process. This paper reviews some of the more important aspects of the decay process in relation to test methodology and then discusses how data are sometimes used b...
B S Goodell, J J Morrell
Method for determining the critical moisture level for mould growth on building materials
2013 - IRG/WP 13-20530
The natural conditions of relative humidity (RH) and temperature (T) in different parts of a building is rarely constant over time. Instead, RH and T often vary cyclically and may pose a risk of mould growth as these conditions are the two key environmental parameters that controls mould growth. Consideration to both humidity and temperature conditions and the susceptibility to mould in a material...
A Ekstrand-Tobin, P Johansson, G Bok
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
System treatments of Pinus sylvestris - influence on moisture, decay and discoloration
2013 - IRG/WP 13-30612
Biological activity can cause challenges for the use of wood in outdoor exposure. Decay and discolouring fungi influence the service life of wooden constructions, and the moisture content of the wood is often an important factor. The aim of this study was to evaluate the performance of different combinations of preservative/modified wood protection treatments and surface treatments for wooden deck...
A Schabacker, G Alfredsen, L Ross Gobakken, H Militz, P O Flæte
Application of a model for the prediction of fungal degradation of thermally modified beech timber by Trametes versicolor
2013 - IRG/WP 13-40622
Colour measurement technology is found to be feasible for characterization of the property changes of thermally modified timber (TMT). In opposite to time-consuming and expensive laboratory tests a non-destructive test represents an improvement for the manufacturer of TMT. Therefore the aim of this study was to develop a method which allows sorting the different treatment intensities after the man...
Clauder, L., Richter S., Unger, W., Pfriem, A
Hygroscopicity of wood after polyethylene glycol (PEG) impregnation and/or heat treatment
2013 - IRG/WP 13-40623
The hygroscopicity of wood after polyethylene glycol (PEG) impregnation and/or heat treatment was investigated by testing the water uptake, equilibrium moisture content (EMC) at various relative humidity levels, and contact angle of the poplar wood surface. The results showed that: (1) At the first moment, the heat treatment at temperatures lower than 160 ℃ did not reduce the water uptake be...
Weiyue Xu Yuan Zhu, Jinzhen Cao