Your search resulted in 100 documents. Displaying 25 entries per page.
Radial flow of Bornmullerian fir (Abies bornmulleriana Mattf.) as affected by wood tapering and the condition of end wall structure of uniseriate ray parenchyma cells
2008 - IRG/WP 08-40441
Amenability to radial permeability of Bornmullerian fir (Abies bornmulleriana Mattf.) was studied on the base of the effects of wood tapering and the structure of end walls of uniseriate ray parenchyma cells. The results showed that the most remarkable culprits of the greatest fluid uptake (as the percentage of void volume filled by the fluid in the radial flow direction, RVVF%) are the lesser woo...
I Usta, S Aslan
Emission Rates of Active Substances from Preserved Wood in Use Class 3
2008 - IRG/WP 08-50256
The evaluation of an active substance or a biocidal product under the Biocidal Products Directive (BPD) requires that an environmental risk assessment is carried out. The risk assessment for wood preservatives includes scenarios for preserved wood (e.g. cladding on a house), in which the
predicted environmental concentration (PEC) in soil is calculated, using an emission rate for the active subs...
E F Baines
To decay or not to decay: An accelerated field test of the validity of the Scheffer index
2008 - IRG/WP 08-20392
The Scheffer Index was introduced in 1971 to predict the relative decay hazard of untreated wood exposed above-ground. Precipitation and temperature parameters are used in the calculation. A higher Scheffer Index value implies a greater risk of decay. An accelerated 18-month study using seven field sites with Scheffer Indices ranging from 35 to 400 and two wood types (Populus tremuloides and Pi...
G M Larkin, P E Laks
Dimensional Stability of Nine Tropical Hardwoods from Cameroon
2009 - IRG/WP 09-10687
This study investigated the swelling behavior, rate of swelling and dimensional stability of nine tropical hardwood species from Cameroon, namely ayous (T. scleroxylon), bilinga (N. diderrichii), bubinga (G. tessmannii), iroko (C. excelsa), Makore (M. heckelii), moabi (B. toxisperma), movingui (D. benthamianus), teak (T. grandis) and zingana (M. brazzavillensis). Continuous swelling was monitored ...
S R Shukla, D P Kamdem
Barefoot-heat-impact of oil-heat-treated wood: An important thermal property of decking boards
2009 - IRG/WP 09-40458
In this study the phenomenon of sensual heat impression was examined, when walking with bare feet on sun exposed wood based decking boards. A suitable method for measuring the heat flux from decking boards into an artificial foot was developed. The method and measuring device is described as well as results from measuring three different decking board materials: Oil-heat-treated spruce (OHT), untr...
A O Rapp, C R Welzbacher, C Brischke
Measurements of rot fungal activity as a function of moisture content by isothermal calorimetry
2010 - IRG/WP 10-20428
Measurements of heat production rate have been made on wood samples with the brown rot fungus Postia placenta at different moisture contents. The results clearly indicate that the heat production rate (a measure of respiration rate and activity) is moisture dependent. When the moisture content is decreased, less heat is produced, and when the moisture content is increased, more heat is produced. I...
L Wadsö, A Pilgård, G Alfredsen
Kinetic Water Vapour Sorption of Sitka Spruce at Variable Temperature Using the Parallel Exponential Kinetics Model
2010 - IRG/WP 10-40512
In this study the water vapour sorption of Sitka spruce (Picea sitchensis (Bongard) Carr.) was measured using a Dynamic Vapour Sorption (DVS) apparatus and then analysed using the parallel exponential kinetics (PEK) model. The water vapour sorption rate of wood quickly increased when the relative humidity was changed. With the elapse of time, the sorption rate gradually decreased within any specif...
Yanjun Xie, C Hill
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
A Review of Radial Flow of the Refractory Softwoods: An Example of Sitka Spruce
2011 - IRG/WP 11-40564
As one of the refractory softwood species, the major problems in the preservative treatment of spruce based on the radial flow relate to the anatomical structure of the wood material. The most important morphological features influencing this were the amount of the nature and the condition of both ray tracheids and ray parenchyma cells, and the cross-field pits in particular. The conducting pathwa...
Ilker Usta, Radovan Despot
In-ground variability of decay intensity within a test field
2012 - IRG/WP 12-20496
Timber exposed in the ground faces most severe conditions in terms of exposure to wetting and fungal decay in the terrestrial environment, therefore wood durability tests are often conducted in test fields preferably ensuring the occurrence of all relevant decay organisms. One can also expect differences in decay within an individual field-test site due to localized distribution of certain organis...
C Brischke, S Olberding, L Meyer, T Bornemann, C R Welzbacher
Effect of growth rate and radial position on the natural durability of Douglas-fir
2012 - IRG/WP 12-10791
In terms of natural durability, Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) fame owns to the favourable characteristics of centuries-old trees harvested in old-growth North American forests. The properties of wood coming from plantations harvested between 50 and 100 years-old are likely to be different. In such stands, plantation density and thinning intensity may have a large impact on the...
C Pollet, J-M Henin, B Jourez, J Hébert
Statistical analysis of durability tests - Part 2: Principles of time-to-failure and application on field test data
2013 - IRG/WP 13-20512
Service life prediction is an important topic in wood research, especially with regard to the Construction Products Regulation (CPR). Both laboratory tests as well as in-service performance testing is therefore essential, in combination with proper monitoring and analysis tools. A crucial concept is variability and the incorporation of variability in tests and analysis. In this paper we focus on t...
J Van den Bulcke, I De Windt, C Brischke, C R Welzbacher, A O Rapp, J Van Acker
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
The activity of a wood-decaying fungus during drying and rewetting cycles measured by isothermal calorimetry
2013 - IRG/WP 13-20526
Wood decaying fungi are an essential part of any ecosystems as they are the main decomposers of cellulose and lignin-containing materials. But as wood is a common building material the risk for decay fungi growth and subsequent degradation of our construction material is a concern. There are important physiological aspects of the growth and activity of decay fungi that are unknown today, and witho...
S Johansson, L Wadsö, A Pilgård, G Alfredsen
Development of a rapid method to assess the rate of fungal colonization of wood
2013 - IRG/WP 13-20531
Testing of wood durability is today done mainly with accelerated exposure tests under rather realistic conditions (in ground, outdoors with moisture traps etc). Although such tests are accelerated with respect to the conditions that outdoor exposed wood structures are exposed to, they tend to take rather long time. The present paper presents the development of a rapid method intended to assess at ...
L Wadsö
Effect of silver nanoparticles on the rate of heat transfer to the core of the medium-density fiberboard mat
2014 - IRG/WP 14-40653
Effect of silver nanoparticles on the rate of heat transferred to the core section of medium-density fiberboard (MDF) mat was studied here. A 400 ppm aqueous nanosilver suspension was used at three consumption levels of 100, 150, and 200 mL/kg based on the weight of dry wood fibers; the results were then compared with the control MDF panels. The size range of silver nanoparticles was 30-80 nm. Res...
H Reza Taghiyari, O Schmidt, E Bari, P M Tahir, A Karimi, P Nouri, A Jahangiri
Transfer of microorganisms from wooden crates to foodstuffs: assessment of a transfer threshold
2016 - IRG/WP 16-20574
Wood is commonly used in contact with foodstuffs, for example for packaging fruits or vegetables. Most common species used are beech, pine, spruce and poplar. Wood is often considered as being less safe than plastic because it is less easy to clean whereas several studies have demonstrated that microorganisms cannot survive easily on wood (Milling et al., 2005; Revol-Junelles et al., 2005). Nation...
M Montibus, R Ismail, I Le Bayon, A Jasick, M Gabille, F Aviat, V Michel, M Federighi, M Kutnik
Combustion and thermal characteristics of Korean wood species
2016 - IRG/WP 16-40727
This study examined the combustion and thermal characteristics of domestic woods in Korea. Wood was confirmed by a cone calorimeter according to the KS F ISO 5660-1 standard. The combustion properties of the wood were measured in terms of the heat release rate (HRR), total heat released (THR), mass lose rate (MLR), and ignition time (time to ignition; TTI). Also, the thermal properties were measur...
Huyun Jeong Seo, Jung-eun Park, Dong Won Son, Won-Joung Hwang
The development of a suitable fire retardant for Radiata pine and other species
2019 - IRG/WP 19-30744
The use of fire retardant chemicals, with the overarching aim of creating a safer environment is not a new one, however it is generally under-developed and is often afflicted with an image of environmental and health issues and misperceived high costs. There is an ever-increasing need and desire for effective fire retardancy in timbers to inhibit or suppress the combustion process. This is paramou...
B R Derham, M R Fortune
Validating a short-term laboratory method to assess the resistance of timber to biodegradation by marine wood-borers
2021 - IRG/WP 21-10975
Novel approaches to protecting wood in coastal and marine environments are needed as the use of traditional broad-spectrum biocides are now restricted. Wood is widely utilised in marine environments where it can be rapidly degraded by wood-boring organisms, causing billions of dollars of damage per annum. Biocidal compounds such as CCA and creosote have been popular treatments for timber products ...
L S Martin, J R Shipway, G P Malyon, S M Cragg
Wood modification reduces the feeding rate of the wood boring crustacean, Limnoria quadripunctata
2022 - IRG/WP 22-10993
Adult Adult Limnoria search for new wood once their current piece disintegrates from tunnelling. During this time, they do not have access to wood so experience a period of starvation and must feed again once settled. Wood modification offers protection to marine structures by reducing the feeding rate of Limnoria and therefore can reduce recruitment of adults from distant pieces of wood. Chemical...
L S Martin, S Lande, M Westin, S M Cragg
A Comparison of Cross-Laminated Timber (CLT) Floor Panels using Finite Element Analysis and Experimental Fire Testing
2022 - IRG/WP 22-40955
Cross-laminated timber (CLT) is a relatively new timber product and has gained popularity in North America and Europe as a construction material. As a sustainable engineered timber product, CLT offers many advantages over solid wood, concrete, or steel construction. However, the use of timber in medium to high rise buildings is often avoided mainly due to its combustible nature. In this paper, a n...
M Yasir, A Macilwraith, K Ruane
Field durability testing of wood above ground - Part 1: 15 years’ experience with the Bundle method
2023 - IRG/WP 23-20695
A ‘jack of all trades’ method for above-ground wood durability testing has been sought for decades, but until now no method has found its way into standardization. The method of choice shall be applicable for untreated and treated wood – ideally also for wood composites. It shall be reproducible, objective, fast, easy, and inexpensive. Finally, it shall provide high predictive power.
This s...
C Brischke, G Alfredsen, L Emmerich, M Humar, L Meyer-Veltrup
Field durability testing of wood above ground - Part 2: The full guideline of the Bundle method
2023 - IRG/WP 23-20696
To determine the biological durability of wood above ground, numerous approaches for test methods have been pursued and tried out in the field in the past. So far, no method has managed to find its way into a European standard. During the last 15 years, experience with the Bundle method has been gained. As described in Part 1 of this paper, the method is recommended as a suitable tool for determin...
C Brischke, G Alfredsen, L Emmerich, M Humar, L Meyer-Veltrup
Characterisation of fungal decay in cable car trestles in Svalbard
2023 - IRG/WP 23-11031
The Arctic will be strongly affected by climate change. In Svalbard the coal mining industry were established in the early 20th century. All man-made structures and sites dating before 1946 in Svalbard are protected by law and considered as cultural heritage. This included the massive cable car trestles that are constructed from untreated Norway spruce and mounted directly into the soil. We hereby...
G Alfredsen, L Ross, M Altgen, I A Yakovlev, A-C Flyen, M S Austigard, J Mattsson, N B Pedersen