Your search resulted in 76 documents. Displaying 25 entries per page.
Modelling of onset of mould growth for wood exposed to varying climate conditions
2009 - IRG/WP 09-20414
A performance-based service life design format based on climatic exposure on one hand and “resistance” of wood against mould growth on the other hand, is presented in this paper. A limit state for onset of mould growth is defined as the occurrence of traces of mould observed by microscopy. A dose-response model is proposed by which onset of mould growth can be predicted for an arbitrary climat...
S Thelandersson, T Isaksson, A Ekstrand-Tobin, P Johansson
Decay hazard mapping for Europe
2011 - IRG/WP 11-20463
In this study, two different dose-response models for above-ground decay as well as a model transferring macro climate data to wood climate data are presented. The models base on data from field trials, which had been conducted at 28 European test sites, and were used to calculate the relative risk for decay caused by climate variability in Europe. The two dose-response models give coherent result...
C Brischke, E Frühwald Hansson, D Kavurmaci, S Thelandersson
Service life prediction of wooden components - Part 3: Approaching a comprehensive test methodology
2011 - IRG/WP 11-20464
This paper is the third in a series on 'service life prediction' of wooden components and should be considered as a discussion paper. The authors tried to analyze the topic with a look from a distance and comment sometimes with a smile on the current controversial discussion about SLP issues. Nevertheless, the viewpoints of different groups, such as natural scientists, engineers, approva...
C Brischke, C R Welzbacher, L Meyer, T Bornemann, P Larsson Brelid, A Pilgård, E Frühwald-Hansson, M Westin, A O Rapp, S Thelandersson, J Jermer
Modelling decay rates of timber exposed above ground on four different continents
2020 - IRG/WP 20-20670
Durability performance data from an international decking trial were analysed to explore relationships with climate variables, particularly those related to temperature and rainfall. Matched decking samples of slash pine (Pinus elliottii) sapwood and heartwood, spotted gum (Corymbia citriodora), Norway spruce (Picea abies) and Scots pine sapwood (Pinus sylvestris) were exposed to the weather above...
L P Francis, J J Morrell, C Brischke, P B Van Niekerk, J Norton
Service life prediction of wooden components – Part 1: Determination of dose-response functions for above ground decay
2010 - IRG/WP 10-20439
Scots pine sapwood (Pinus sylvestris L.) and Douglas fir heartwood (Pseudotsuga menziesii Franco) specimens were exposed in double layer field trials at 24 different European test sites under different exposure conditions (in total 28 test sets). The material climate in terms of wood moisture content (MC) and wood temperature was automatically recorded over a period of up to eight years and compar...
C Brischke, A O Rapp
Performance of Creosote/Chlorothalonil Preservatives
2011 - IRG/WP 11-30580
The addition of chlorothalonil to P2 creosote was found to increase the durability of southern pine in a series of ground contact stake tests. At retentions lower than those specified in the AWPA Standards, performance was increased when the creosote was amended with chlorothalonil. This indicates that lower creosote retentions may be required for as good or better ground contact when the amende...
H M Barnes, M G Sanders, G B Lindsey, T L Amburgey
Development of decay hazard maps based on decay prediction models
2016 - IRG/WP 16-20588
Durability plays a very central role in timber engineering, especially when working with wood in use class 3 and above where the risk of decay is high. As one of the primary decay influencing factors, the external condition, i.e. the local climate, is often graded by some type of climate index value. Predominately, climate indices are based on a direct relationship between weather data and decay. ...
J Niklewski, E Frühwald Hansson, C Brischke, D Kavurmaci
Studies into the effect of soil type and soil layer on the in-ground decay of European beech
2022 - IRG/WP 22-20681
In this study, European beech (Fagus sylvatica L.) specimens were exposed to three different soil types; Podsol (Podzol), Braunerde (Cambisol), and Pararendzina (Regosol), in adapted terrestrial microcosm (TMC) tests according to CEN/TS 15083-2 (2005). Soils were sampled (250 mm deep) from field sites and separated into their constituent layers to deliver three TMC setups; mineral soil layer only ...
B N Marais, S Kovacs, M Jansen, C Brischke
Simulations of microclimates for wood-decaying fungi in the built environment using environmental analysis
2023 - IRG/WP 23-20703
Simulations of fungal decay risk were run on two similar building geometries exposed to typical annual climate conditions of two different geographical locations, Brunswick (Germany) and Cairns (Australia). The simulations were conducted to capture the effect of wind-driven rain and solar irradiation exposure over nodes of the common building geometry. The moisture content and temperature variatio...
P B van Niekerk, J Niklewski, S H Hosseini, B N Marais, I Frimannslund, T Kringlebotn Thiis, C Brischke
Comparative response of Reticulitermes flavipes and Coptotermes formosanus to borate soil treatments
1991 - IRG/WP 1486
Eastern (Reticulitermes flavipes [Kollarl]) and Formosan (Coptotermes formosanus Shiraki) subterranean termite workers (Isoptera: Rhinotermitidae) were exposed to borate-treated sand in an indirect exposure tunneling assay in the laboratory. In the ten day assay period, both termite species readily penetrated sand containing 5000, 10000, or 15000 ppm (wt. of compound / wt. of sand) disodium octabo...
J K Grace
The effect of certain wood extractives on the growth of marine micro-organisms
1977 - IRG/WP 438
S E J Furtado, E B G Jones, J D Bultman
Modelling of PCP migration in the environment: Feeding the models with laboratory data
1993 - IRG/WP 93-50001-08
In 1989, Hydro-Québec began a study program on pentachlorophenol (PCP) to ensure safe use of the product at all stages. One of the aspects of the study is the creation of a predictive system for evaluating the behavior of PCP and oil migration from wood poles to the environment. This system comprises four mathematical models for predicting PCP and oil migration in and on the surface of the pole, ...
A Besner, P Tétreault, R Gilbert
Response of the Formosan Subterranean Termite (Coptotermes formosanus) to Cellulose Insulation Treated with Boric Acid in Choice and No-Choice Tests.
2004 - IRG/WP 04-10532
The tunneling ability of the Formosan subterranean termite Coptotermes formosanus Shiraki through a cellulose insulation material containing11.1% boric acid was tested in choice and no-choice bioassays. We examined tunneling behavior and mortality of termites exposed to treated and untreated insulation material in miniature simulated wall voids. In a choice test termites tunneled through untreat...
M E Mankowski, J K Grace
Response of laboratory groups of Reticulitermes speratus (Kolbe) to different quantities of food
2003 - IRG/WP 03-10489
As part of a project aimed at improving understanding of the foraging biology of Japan’s most widespread wood-destroying termite, different sized groups of Reticulitermes speratus (0.5; 1 and 2 g) from two colonies were kept on 16 or 64 cm3 of sapwood of Cryptomeria japonica for 12 weeks in the laboratory. Patterns of wood consumption, wood consumption rates and survival are discussed....
M Lenz, T Yoshimura, K Tsunoda
Rates of emission from CCA-treated wood in the marine environment: measurement, modelling and requirements for further research
2001 - IRG/WP 01-50166-12
Accurate estimates of rates of emission of leachate from preservative treated wood are crucial for realistic predictions of the environmental impact of its use in maritime construction. Estimates are available for some commonly used preservatives, but these vary widely. Though variable, these measurements suggest that emission generally decreases exponentially with time. Part of the variation is d...
S M Cragg, C J Brown, R A Albuquerque, R A Eaton
Système informatisé d'aide à la décision pour la gestion de la migration du pentachlorophénol dans l'environnement
1993 - IRG/WP 93-50001-10
This paper describes a Decision Support System (DSS), concerning pentachlorophenol (PCP) migration in the environment. The principal objectives of the DSS are to assist managers in siting of PCP-treated poles in the Hydro-Québec system and the storage areas and in the treatment of customer complaints. Four mathematical models are incuded in the system: a model simulating migration inside and on t...
G Lefebvre, J-C Tessier
Kinetic modelling of adsorption of quaternary ammonium compounds by Scots pine wood sawdust (Pinus sylvestris L.)
2005 - IRG/WP 05-30369
The adsorption of new quaternary ammonium compounds from aqueous solutions onto Scots pine wood (Pinus sylvestris L.) sawdust was studied. The pseudo first- and second- order kinetic models were used for the mathematical description of the sorption dynamic process of QACs onto wood. The highest correlation coefficients were obtained for the pseudo-second order kinetic model, those suggest that che...
J Zabielska-Matejuk
Preservative absorption response of planks of Anogeissus acuminata for plank-built catamarans
2002 - IRG/WP 02-40245
Due to shortage of timber coupled with other compelling factors, traditional fishermen along the east coast of India, especially of Andhra Pradesh, of late, are departing from conventional log type wooden catamarans. Instead, they are fabricating catamarans out of timber planks of hard woods and utilizing thermocol for buoyancy. Mostly, locally available timber of a Combretaceae species, Anogeis...
V Kuppusamy, M V Rao, M Balaji, K Rao
Methods for testing fumigant efficacies against termites
1986 - IRG/WP 1297
Methodologies for testing fumigants against termites are reviewed and factors needed to be taken under consideration for standardization listed. Toxicity should be defined by both direct exposure to the gas and under more practical "barrier" conditions which include test enclosures simulating abiotic surroundings of the termites, i.e. wood, nest material, etc. To observe latent effects, mortality ...
N-Y Su, R H Scheffrahn
Subterranean termites in Portugal. Tentative model of distribution
2002 - IRG/WP 02-10420
Although extensive references can be found on the presence in the last 50 years of Reticulitermes lucifugus (Rossi), in Portugal, its exact distribution and importance has never been critically evaluated.
Termites were found to be widespread in the country and are probably the most serious wood destroying insects in buildings.
To provide a future working tool that would permit an evaluation of t...
T Nobre, L Nunes
Testing a diffusion and reaction model for the leaching of CCA components from unfixed CCA-treated wood
2002 - IRG/WP 02-50193
A previously described physical model applicable to the leaching of any substance undergoing a first-order fixation reaction with wood is applied to the leaching of CCA components from unfixed wood. Using this model and laboratory leaching experiments with small wood samples immersed in water, the diffusion coefficients and reaction rate constant of Cr6+, total Cr, Cu and As in unfixed CCA-treated...
L Waldron, P A Cooper
Positive dosage response of CCA in hardwood power poles to soft rot indicated from New South Wales soft rot survey dat
1983 - IRG/WP 3233
Experience and observation have shown that retentions of less than 16 kg/m³ in the sapwood of individual hardwood poles are unlikely to delay its deterioration sufficiently to ensure an economic performance in some instances. The higher retentions of current practice should do so subject to adequate inspection and maintenance. Increases in retentions requirements up to 35 kg/m³ more or less, dep...
A J Witheridge
Physiologic response of Phanerochaete chrysosporium to exposure to triazole fungicides
1994 - IRG/WP 94-10066
Triazoles are increasingly important fungicides which are employed for a variety of applications included wood protection. Several recent studies suggest that white rot fungi are more tolerant of triazole compounds than other wood degrading fungi. Cultural studies using a white rot fungus, Phanerochaete chrysosporium, and 0.2 or 0.8 ppm of tebuconazole or propiconazole suggested that mycelial dry ...
J J Morrell, R K Velicheti
An engineering model for the decay of timber in ground contact
2003 - IRG/WP 03-20260
To predict the residual strength of an engineered structure, it is first necessary to predict the effect of decay. A model was developed in which the effective area of structural decay in large section timbers was defined as that area that could be picked out with a pen-knife. Some limited studies indicated that for practical purposes the remaining wood could be assumed to have its full residual s...
R H Leicester, C-H Wang, M N Nguyen, J D Thornton, G Johnson, D Gardner, G C Foliente, C MacKenzie