Your search resulted in 237 documents. Displaying 25 entries per page.
Mercury porosimetric evaluation of the impregnability of wood
1985 - IRG/WP 2234
Mercury porosimetric measurements for specimens of a given length can not be used to evaluate the treatability of wood. The reason is that the permeability for low permeable woods deviates from Darcy's law with the specimen length. This paper presents a method of evaluation which respects this phenomenon in indicating not only pore size but also a factor describing the pore size as a func...
J P Hösli
Antisapstain field trials of NeXgen in New Zealand
1997 - IRG/WP 97-30145
This document covers the results of summer and winter log trials of NeXgen, an antisapstain formulation containing methylene bis thiocyanate plus chlorothalonil. Log billets (20 - 25cm diameter) were stripped of bark using a commercial maul debarker and antisapstain treated within 8 hours of felling by dip application. Billets were stored in a pole barn and assessed for internal sapstain and decay...
R N Wakeling, T L Woods, D R Eden, C M Chittenden, B Carpenter
Effect of species composition of preservative-treated Douglas fir plywood on its decay resistance
1978 - IRG/WP 2114
Plywood is now commonly used for constructional purposes in environmental situations where decay by wood-destroying fungi can be a considerable risk. However there seems to be a lack of understanding of the relative durability of plywood, both untreated and when treated with wood preservatives. Part of the reason for this situation has been the difficulty of carrying out laboratory decay tests on ...
R S Smith, P Balcaen
Evidence for actinomycete degradation of wood cell walls
1990 - IRG/WP 1444
Several unique patterns of degradation occurring in wood cell walls have been observed in wooden stakes inserted in unsterile soil in the laboratory. Some of the patterns have also been observed in coniferous wood taken from forest floors. All the observed attack types occur within wood cell walls, mainly within the S2 layer. Attack is characterised by channels of varying diameter or small fusifor...
T Nilsson, G F Daniel, S L Bardage
Bending properties of wood after its decay with Coniophora puteana and subsequent modification with selected chemicals
1999 - IRG/WP 99-40146
Mechanical properties of wood are often decreased due to decay processes caused by biotic and/or abiotic factors. Damaged wooden elements (e.g. historical structures) can be reinforced by more methods, including their modification with convenient chemicals. This paper presents influences of selected chemicals on basic bending properties (modulus of elasticity - MOE, modulus of rupture - MOR) of so...
L Reinprecht, S Varinska
Evaluation of bending strength by non-destructive methods of Ezomatzu with white pocket rot
1991 - IRG/WP 2371
The possibility of application of three non-destructive methods was examined for evaluation of bending strength of ezomatsu (Picea jezoensis CARR.) with white pocket rot. As non-destructive methods, the measurements of ultrasonic wave propagation time, impact-induced stress wave propagation time and penetration depth of pin of "PILODYN Wood Tester" were applied to compare with visual evaluation of...
T Tanaka
The development of blue stain in service in sapwood of European softwood species
1997 - IRG/WP 97-10236
The utilisation of softwood species for window joinery applications is gaining importance in countries frequently using tropical hardwood species up to now. Since wood preservation is not always part of the total concept of window frames manufactured from sapwood containing wood elements it is essential to know the impact of durability on the performance. Moisture content control is a major tool i...
J Van Acker, R Klaassen, H Militz, M Stevens
Fungal decay of acrylate treated wood
2004 - IRG/WP 04-30357
Natural durability of wood species is variable. Chemical wood preservatives, such as biocides are necessary for extension of their service life. Many methods have been developed to increase the resistance of wood and wood products against wood-destroying organisms during the last years. The most frequently used methods are chemical and thermal modification of wood. In wood modification the basic c...
Z Tiralova, L Reinprecht
Specifying preservative-treated resistant timber: Conforming to European Standards
2001 - IRG/WP 01-20235
The most common construction timbers used in the UK are of low natural durability and, generally, resistant to preservative treatment. These include species of spruce, hemlock and fir. However, their characteristically limited and non-uniform uptake of preservatives may still confer sufficient protection to give satisfactory durability performance in terms of biological resistance. This paper desc...
E D Suttie, A F Bravery, T B Dearling
Influence of the decay of spruce chips by the selected fungi on their chemical structure and the pulp properties
2004 - IRG/WP 04-10510
The paper focuses on changes in the weight and in the molecular structure of spruce chips submitted to long-term storing as well as to medium- and long-term model rotting degradation caused by some chosen fungi identified at storing processes on the pile. For the model decay of chips under laboratory conditions during 3 or 6 weeks the white-rot fungi: Phanerochaete chrysosporium, Heterobasidion an...
R Solár, L Reinprecht, A Geffert, F Kacík
Proposal for a method aiming at the quantification of the impact of wood extraction in Life Cycle Assessment
1998 - IRG/WP 98-50113
Life Cycle Assessment has been accepted as an instrument for the assessment of the environmental impact of products. Characterisation factors for impact assessment of emissions from products have been established. To date no characterisation factor exists for the extraction of biotic resources, for example wood. Since the main disadvantage of using wood as a material lies in the extraction of reso...
P Esser, E Van der Voet
Bending strength of heat-treated spruce and pine timber
2002 - IRG/WP 02-40242
Heat-treatment of spruce (Picea abies) and pine (Pinus sylvestris) beams (45 x 145 mm) gave a reduction in bending strength of approximately 50%. The bending stiffness (modulus of elasticity) only decreased by 3.5%. Tests were carried out according to EN 408. Another effect of the heat-treatment was increased variation in bending strength. The 5th percentile value of the bending strength, the so c...
C Bengtsson, J Jermer, F Brem
Studies in an accelerated soil bed facility on the decay susceptibility of U.K. grown spruce and pine poles treated with copper/chrome/arsenic (CCA) by pressurised sap-displacement. Part 1: Setting up of soil beds and initial soft rot results
1990 - IRG/WP 2344
The paper describes the methodology used in the construction and early operation of an accelerated soil bed facility used to examine the decay susceptibility of U.K. grown Scots and Corsican pine and Sitka and Norway spruce treated with C.C.A. by high pressure sap-displacememt. The design and control of the facility as well as the preparation, soil exposure and soft rot decay analysis of quarter p...
A Bruce, S D Hainey, G M Smith, B King, P D Evans
Methods to determine the efficacy of three water repellent additives in waterborne preservatives
1997 - IRG/WP 97-30142
The paper describes the methods used to determine the efficacy of three different water repellent additives in waterborne preservatives. The wooden samples used are pine (Pinus sylvestris) and spruce (Picea abies) that are treated with 9 different waterborne preservatives in retention for hazard class 3 (above ground commodities). There are two sample sizes exposed, cladding boards (19 x 148 mm) w...
F G Evans, B Nossen, K M Jenssen, L R Wilhelmsen, G Fuglum
Application of oscillating pressure to improve treatability of refractory species
1987 - IRG/WP 3449
Under practical conditions a minimum moisture content of 80% demande by the German quality standard RAL-RG 411 can not be guaranteed throughout the year. Storage of logs with bark prolonges the drying process; a storage without bark must be avoided. A sufficient penetration according the standard can be achieved at least with a moisture content of 60%, optimal conditions may prevail between 100% a...
R-D Peek
An investigation of the nutritional physiology of the wood-boring weevil Euophryum confine Broun
1994 - IRG/WP 94-10082
The digestion of Picea abies Karst and Pinus sylvestris L. by Euophryum confine, at two sites is reported in this study. The composition of sound wood, wood from the heads of the weevil tunnels and the frass egested has been determined by gravimetric analysis. A comparison of sound wood and wood ingested showed that weevils tunnelled in microbially decayed wood, while a comparison of the wood inge...
A J Pitman, S M Cragg, G S Sawyer
The study of blue stain found in coniferous timber in SR Slovenia (Yugoslavia)
1983 - IRG/WP 1177
The report concerns the problems connected with blue stain in coniferous timbers stored in warehouses at wood-processing plants in SR Slovenia (Yugoslavia). The amounts of spruce-wood (Picea abies Karst.) found to have been infected with blue stain have been measured and some of the fungi causing the stain have been identified and their biology studied. It was found that the percentage of spruce-w...
R Benko
Formosan Subterranean Termite Resistance to Heat Treatment of Scots Pine and Norway Spruce
2003 - IRG/WP 03-40264
New challenges to the durability of wood building materials have arisen in the U.S. The Formosan subterranean termite (Coptotermes formosanus Shiraki) now infests sizable portions of the U.S. south and their range is extending. Heat treatments offer a unique opportunity for wood-based composites because many of the process techniques already employ various thermal applications and could be easil...
W R Smith, A O Rapp, C R Welzbacher, J E Winandy
Whitewood - An external joinery timber?
1975 - IRG/WP 253
The timber used traditionally for softwood joinery in the UK is redwood (Pinus sylvestris). In the past its ready availability in the desired sizes and quality and its durability in service encouraged little competition. However, the past decade has seen some erosion of this position, particularly through the increased proportion of sapwood in redwood supplies. Since the sapwood is less durable th...
J W W Morgan
Water transfer in wood in relation to fungal attack in building - Effect of condensation and diffusion
1992 - IRG/WP 92-1543
Wood is continuously exchanging moisture with the surrounding atmosphere, the temperature and relative humidity are important factors. Wood moisture in this case is not enough to provoque decay by fungi. However, when, during the night, condensation appears cyclically, wood absorbs water and moisture content may be sufficiently high to allow development if drying does not take place. The water tra...
D Dirol, J-M Vergnaud
Preliminary indications of the natural durability of Spruce bark board
1999 - IRG/WP 99-10312
A board material made from pressed bark, with no added adhesive, has been developed by Forintek's composites group and tested for durability by Forintek's treated-wood group and the University of Hawaii. This material was also manufactured with veneers in a one-step process. Since one role of bark on the tree is protection against pests and diseases, barkboard was expected to hav...
P I Morris, J K Grace, G E Troughton
Influence of fungal exposure on the redistribution of copper in treated spruce wood
2002 - IRG/WP 02-10450
The redistribution of copper in treated wood after exposure to basidiomycete decay fungi is described. The micro-distribution of copper in copper(II) sulphate or copper(II) octanoate/ethanolamine treated Norway spruce wood before and after exposure to 3 different wood decay fungi was studied using transmission electron microscopy with X-ray microanalysis. The copper content of the mycelium and the...
M Humar, F Pohleven, R J Murphy, D J Dickinson, I Moris, M Zupancic, P Kalan, M Petric
The resistance of wood coated with different water-borne paints against colonisation by decay fungi
1996 - IRG/WP 96-10165
The susceptibility of wood painted with model paints of known composition to decay fungi was tested without previous weathering. Included in the study were five alkyd emulsion paints and five acrylic paints; one linseed oil paint and two solvent-borne alkyd paints. It was found that several components influenced the susceptibility of these paints. The results of the present study indicate that the...
J Bjurman
New method to find out the volatile organic compounds (VOC) of wooden material
2000 - IRG/WP 00-20189
Volatile organic compounds (VOC) of pine, spruce and larch wood were studied using a new technique developed at VTT Chemical Technology. 50 mg of crushed wood material was placed into glass tubes. The tubes were closed with a glass wool, which is pressed with a tube cap. Wood samples were analysed with a gas chromatograph after thermal desorption using four different temperatures (50°C, 100°C, 1...
H Viitanen, K Villberg, K Saarela
Correlation between modulus of elasticity, mass losses and FTIR spectra of copper treated decayed wood
2006 - IRG/WP 06-10580
The composition of copper-based preservatives will change from copper-chromium to copper-ethanolamine, due to environmental demands. The most important drawback of copper-impregnated wood is the presence of tolerant fungal organisms that have developed an ability to degrade such preserved wood. In order to elucidate these processes, specimens (0.5×1.0×15 cm) made of Norway spruce (Picea abies) w...
M Humar, B Bucar, F Pohleven