Your search resulted in 207 documents. Displaying 25 entries per page.
Effect of fungal attack on maximum load capacity of simulated wall assemblies
2007 - IRG/WP 07-20363
The effects of moisture intrusion and fungal attack on the maximum load capacity of nailed assemblies was investigated using one white and one brown rot fungus against 4 material combinations over a 20 week period. Wetting significantly reduced the maximum load capacity of all four material combinations, while wetting and autoclaving only affected the OSB sheathing/spruce stud. The white rot fung...
N Melencion, J J Morrell
Copper fixation in ACQ-D treated Chinese fir at various temperature and relative humidity conditions
2007 - IRG/WP 07-30436
In this study, the effect of different conditions of temperature, relative humidity, and duration of post-treatments on accelerating copper fixation in ACQ-D treated Chinese fir wood blocks was investigated. The conditions include the combination of three temperatures (21, 50, and 70?) and two relative humidity levels (20% and 80%), also include four temperatures (50, 70, 90, and 110?) without con...
Jinzhen Cao, Lili Yu
Durability of timber from exotic species against termite attack in Indian conditions
2007 - IRG/WP 07-10629
Exotic trees species, Acacia mangium Willd. and A. auriculiformis A. Cunn. ex Benth. and their hybrid are widely grown in India for multiple uses including use as timber. It is essential to know the natural durability of timbers against termites for predicting the service life of the timber and deciding on the application of preservatives to enhance the durability. Studies were conducted to test t...
O K Remadevi, R Muthukrishnan
Preventing Xylosandrus crassiusculus Beetle Attack in Large Green Timbers Using Pyrethroid Dip Treatments
2008 - IRG/WP 08-10642
Although awareness about the risk of invasive species has increased over the past decade, a large number of highly destructive exotic pests are still being introduced around the world. One of the more important pest introductions in the Southeastern United States has been the Asian ambrosia beetle, Xylosandrus crassiusculus. This species is particularly important
because of its ability to kill...
C Schauwecker, A F Preston, J J Morrell
Wood boring species present in the Tagus Estuary and the severity of their attack on wooden piles exposed in the area: a case study
2008 - IRG/WP 08-10664
Wood exposed in the marine environment is subject to degradation by wood boring organisms. This is probably one of the reasons why wood has been substituted by concrete and steel in maritime structures in many European coastal areas. Wooden piles obtained from a wharf exposed in the Tagus Estuary, Porto Brandão (Almada, Portugal) provided an opportunity to understand the main
agents of biodeter...
L M S Borges, L Nunes, A A Valente, P Palma
Whole-of-house protection from subterranean termite attack and damage after four years of field exposure
2008 - IRG/WP 08-10665
This study reports the condition of the whole-of-house termite protection test in tropical Australia after four years. The study was designed to provide maximum protection to whole-of-house timbers in a natural situation posing the highest hazard from subterranean termite populations. The houses were constructed either on concrete slabs or suspended floors using untreated and treated timber fram...
B M Ahmed (Shiday), J R J French, S R Przewloka, P Vinden, J Hann, C Y Adam
A preliminary note on the role of moisture absorption rate in durability assessment
2008 - IRG/WP 08-20383
The rate of moisture uptake was studied in 15 wood species using vermiculite at varying moisture levels as the exposure medium. As might be expected, moisture uptake varied widely among the species studied. While some of the more durable wood species were also resistant to moisture uptake, this was not always true. The results are discussed in relation to performance in under varying environmenta...
J J Morrell, L P Francis
Primary Study on Compressed Preservative-treated Wood (CPW) for Outdoor Applications
2008 - IRG/WP 08-40412
In this study, the compressed wood samples pre-treated with hot water bath or water spraying were immersed in the ammoniacal copper quat –type D (ACQ-D) preservative solution to get compressed preservative-treated wood (CPW). The liquid absorption and the recovery rate of compression deformation of the compressed wood was determined, as well as the surface hardness, the distribution of density a...
Jinzhen Cao, Jia Mao
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
Fungal Attack on Lignin and Cellulose: Elucidation of Brown- and White-Rot Mechanisms Comparing Biomimetic and In-Vivo Degradation Patterns
2010 - IRG/WP 10-10714
This paper examines research and hypotheses that have been developed over several years on wood degradation mechanisms. This information is combined with new data and analyses to explain why wood decay patterns caused by brown-rot fungi and specific types of white-rot fungi are different. New data, including work with both biomimetic studies on low molecular weight compounds, degradative enzymes, ...
V Arantes, B Goodell, A M F Milagres, Yuhui Qian, T Filley, J Jellison, S Kelley
Control of Reticulitermes grassei as a pest in Spain: Termite distribution in an urban area
2010 - IRG/WP 10-10719
The European subterranean termite Reticulitermes grassei Clément, 1978, has been an important pest in Palenciana, a locality in the southern province of Cordoba (Spain) for a long time. The different stages of the pest elimination process have been studied and are presented here. Firstly, a through inspection of all town dwellings was conducted in order to determine a theoretical affected area of...
E Alcaide, R Molero, J Diz, M Gaju
Estimating the age of subterranean termite attack and damage in buildings
2010 - IRG/WP 10-10727
This paper describes physical and experimental methods and a mathematical model (Rotramel 2003) to assist in estimating the age of subterranean termite attack and damage to building structures. Timber, building and termite management industries have to develop new strategies to assess and estimate termite attack and damage in the current climate of global warming. A case study will be used as an e...
J R J French, B M Ahmed Shiday, J Thorpe
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
Effects of polyvinyl alcohol on leachability and efficacy of boron wood preservatives against fungal decay and termites attack
2010 - IRG/WP 10-30526
In this study, the use of polyvinyl alcohol (PVA) as boron fixative agent was investigated. Two levels of PVA (2.5 and 4%) were evaluated with disodium octaborate tetrahydrate (DOT) at three concentrations (1, 2 and 4% boric acid equivalent (BAE) using a double vacuum impregnation processes on Scots pine sapwood specimens. Leaching was performed according to a laboratory leaching procedure. Boron ...
A Mohareb, M F Thévenon, E Wozniak, P Gérardin
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
Impact of wood species on the performance of exterior wood coatings
2010 - IRG/WP 10-40519
To prolong the service life of a wooden construction the protective function of a coating is of utmost importance. The chemical composition as well as the wood-coating interface affects the performance of this protective layer and obviously wood species have an impact too. This paper discusses the influence of wood species on the overall coating performance. Therefore, a range of opaque waterborne...
I De Windt, J Van den Bulcke, J Van Acker
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
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
Biological performance of wood- and bamboo-polypropylene composites: Effects of particle content, particle size and Zn borate
2012 - IRG/WP 12-40577
Particle content and size of wood material in wood plastic composites (WPCs) can affect efficacy of WPCs against fungi and termites. This study evaluated fungal and termite resistance of WPCs manufactured by using two different levels of particle content (50 and 70%) and three different particle sizes (30, 60, and 100 mesh). In fungal resistance tests, Tyromyces palustris, a standardized test fung...
S N Kartal, S Aysal, E Terzi, T Yoshimura, K Tsunoda
Efficiency of the Amazon Forest Oils as Preservatives to the Attack of cellulolytic fungi in Pine Wood
2012 - IRG/WP 12-30599
The bobbins of wood are used for storage and field installation of cables from the electricity and telecommunications sectors. There are legal requirements governing the Brazilian ways of treating the wood used in these sectors, aimed at preventing pollution and protecting nature. When exposed to severe environmental conditions in Brazil these products are degraded and occurs many operational prob...
S Silveira, I M S Mendes, R S Paiva, J E Volponi, R C G Comar, R S Cruz
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