Your search resulted in 284 documents. Displaying 25 entries per page.
Test Methods – Performance Based Requirements
2004 - IRG/WP 04-20297
In this paper is briefly described the present approach to service life prediction as an essential part of the architectural engineering process. The system of testing the durability of wood is described more in detail including laboratory tests as well as field trials. It is concluded that the system has a lot of weaknesses which makes it less well suited for practical building applications. A le...
M-L Edlund, F Englund, J Jermer, T Nilsson, M Westin, K Ödeen
Preservative performance of copper naphthenate (SANPRESER-OGR) in brush treatment of timber
1991 - IRG/WP 3663
Preservative efficacy of copper naphthenate (SANPRESER-OGR) was evaluated in the laboartory and field trials when timber was treated by brushing. Results of field trial indicated that service life of the brush-treated timber could be approximately 10 years or longer under ground contact conditions, although life span was slightly varied with timber species and test sites. After four years&apos...
Y Sugai, K Hamada, M Kitada, K Tomoi
A new model for wetting and drying of wood end-grain – with implications for durability and service-life
2011 - IRG/WP 11-20477
New experimental data for wetting and drying of wood end-grain, Sandberg (2009), imply that traditional models for moisture transport are not at all applicable. A new model is developed to consider the phenomenological behaviour of water transport in and out of end-grain, using the pore water pressure and sorption scanning properties. Modelling results are compared to experimental results and the ...
L-O Nilsson, K Sandberg
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
Serviceability modeling-Predicting and extending the useful service life of FRT-plywood roof sheathing
2000 - IRG/WP 00-20210
One of the most, if not the most, efficient methods of extending our existing forest resource is to prolong the service life of wood currently in-service by using those existing structures to meet our future needs (Hamilton and Winandy 1998). It is currently estimated that over 7 x 109 m3 (3 trillion bd. ft) of wood is currently in service within the United States of America (PATH 1999). Research ...
J E Winandy
Fungus cellar testing as an evaluation method for performance of treated timber in ground contact
2001 - IRG/WP 01-20227
A fungus cellar method for the accelerated evaluation of performance of treated wood in ground contact is described. The test soil comprised of sandy loam, vermiculite and Japanese horticulture soil "Kanumatsuchi" in a ratio of 6:2:2 by volume. The soil was inoculated with the dominant test fungus isolated with selective medium from decayed wood samples. Pairs of treated and untreated wood specime...
Y Nagano
Butt-end incising to improve penetration and retention of creosote in Eucalyptus saligna power transmission poles in Kenya. Preliminary results
2002 - IRG/WP 02-40249
Incising as a possible technique to improve penetration and retention of creosote in the butt end of Eucalyptus saligna power transmission poles in Kenya was investigated. Debarked, butt-end samples from whole poles were seasoned (15% MC), incised using four patterns of incisions, sealed at the top or small diameter end, and pressure treated with a mixture of creosote-furnace oil (60/40 mix) at a...
R Venkatasamy
Service life of pressure treated deckings of spruce in direct contact with the ground
1988 - IRG/WP 3463
For decking outdoors in Sweden, pressure treated Scots pine (Pinus sylvestris L.) is used, on account of its treatability. The feasibility of using instead the refractory Norway spruce (Picea abies Karst.) is tested in a field trial. The spruce decks were treated together with pine decks with an ordinary Bethell process. As yet, after more than four years of exposure, neither in the battens nor in...
J B Boutelje, T Sebring
Butt-end incising to improve penetration and retention of CCA in Eucalyptus saligna telegraph poles in Kenya: Preliminary results
2002 - IRG/WP 02-40243
Incising to improve penetration and retention of Copper Chrome Arsenate (CCA) in the butt end of Eucalyptus saligna telegraph poles was investigated. Debarked, seasoned (15% MC) butt-end samples from full size telegraph poles were incised using four patterns of incisions, sealed at
the top or small diameter end, and pressure treated, together with un-incised samples, with CCA-C (3.0% oxide typ...
R Venkatasamy
A serial exposure technique for estimating probable service life of treated timber
1978 - IRG/WP 2111
This paper briefly describes part of our preliminary work aimed at developing a test procedure that culd be adopted as a standard method. A detailed version of the work has been submitted for formal publication. In both papers, the aim is to promote interest in extended laboratory testing of wood preservatives. It is believed that this work may provide the basis of a laboratory test procedure from...
J A Butcher
Alternatives to CCA for ground contact protection of timber: a perspective from UK on performance and service life expectations
2002 - IRG/WP 02-30289
The proposed amendment to the European Union's Marketing and Use Directive (1976/769/EEC) in respect of arsenic in CCA wood preservatives seeks to restrict the use of CCA across the European Union. CCA is an extremely important wood preservative in the UK from the manufacturing of the product to the extent of use of CCA-treated timber. Based on our experience and judgement on the use of ...
E D Suttie, A F Bravery, T B Dearling
Natural durability, density and extractive contents of 42 wood species of Bangladesh.
2003 - IRG/WP 03-10490
Natural durability, density and major extractive contents of 42 lesser used or unused wood species of Bangladesh have been studied. Correlation analysis between these properties has been performed. It has been shown that natural durability of these species neither explained by water soluble nor by alcohol benzene extractive contents. Density has a weak but significant positive correlation with dur...
S Akhter, K Akhter, S C Das
Effect of kerfing on performance of Douglas-fir utility poles in the Pacific Northwest
1990 - IRG/WP 3604
Preservative treatment produces an external layer of protection in Douglas-fir poles, but the development of deep checks as the wood dries after treatment can permit entry by fungi and insects. A variety of remedial treatments can arrest this decay; however, it is far more efficient to prevent checking. Kerfing represents one potential method for limiting the development of deep checks. In previou...
J J Morrell
Service life of outdoor wooden constructions. Expectations of private house owners in Sweden
2001 - IRG/WP 01-10401
Wood is traditionally used in indoor as well as outdoor applications. However, if not kept dry, wood is easily attacked by wood degrading micro-organisms. Thus the service life is heavily affected by construction design, choice of wood and wood treatment. For most constructions there is an expected service life. The expectations concerning wooden constructions and what kind of wood is chosen to fu...
M-L Edlund, J Jermer
Quality assured wooden sidings - Criteria, performance evaluations and current status
2000 - IRG/WP 00-20216
Quality assured wooden sidings were brought to the Swedish market in 1998. The system was worked out during a six year period in a close cooperation between the sawmill industry and several research institutes. Centuries of use have given a wealth of experience of spruce boards as a siding material, showing that it works well in most cases but also that its longevity is highly variable, depending ...
F Englund, I Johansson, J Ekstedt, R Nussbaum
Preservative treatment of rubber wood (Hevea brasiliensis) to increase its service life
2005 - IRG/WP 05-40320
Rubber wood (Hevea brasiliensis) possess excellent properties for interior designing, wood working and furniture making. But it is very much susceptible to sap stain and mould fungi which decreases the service life. For profitable uses , it is necessary to increase the service life of rubber wood. To protect the rubber wood from wood degrading agents, the sawn timber were treated with Borax – b...
K Akhter
Deterioration of wood viewed from iron nail
1991 - IRG/WP 2368
Deterioration of nail was graded by a five - rank numerical - rating. The rating of nail moisture content and decay of wood were inspected in a mortal-wall of 34-year-old house. The wood was mostly in decay, when the rating of the nail was above about 4, and the moisture content was above about 20%. Nailed wood specimens kept in several humidity room of 20°C for 4 years showed that the rating of ...
H Imamura
Service Life Prediction of Wood Claddings by in-situ Measurement of Wood Moisture Content
2004 - IRG/WP 04-20304
The Danish Technological Institute is in co-operation with industry partners running a project aiming at predicting the service life of different wood protecting systems.
The project focuses on examining the moisture reducing effect of different wood claddings and the ability to maintain the appearance of the surfaces, when the wood is used in service class 3.
A façade construction is exposed t...
B Lindegaard, N Morsing
Comparison of the anti-fungal efficacy of Cobra with drill perforation on oscillating pressure treated spruce transmission poles -Laboratory test
1988 - IRG/WP 3469
A laboratory method for measuring the depth of penetration of the fungicidal concentrations effective against basidiomycetes (brown rot) was developed. The tests on CCB oscillating pressure treated spruce transmission poles have shown that the depth of salt penetration can be increased by about 10 mm by a drill perforation before the impregnation. An even better penetration is reached, however, if...
E Graf, B Zgraggen
Some fundamental thoughts on the prediction of field performance from lab-testing based on comparison of lab and field test results of some copper-free materials
2003 - IRG/WP 03-20269
In the paper results from lab testing (ENV 807 and EN 113) are compared with field results (EN 252) of differently treated wood. Depending on the type of the organic biocide containing material and depending on type of soil and type of decay differences were found in suitability of the lab methods to predict field performance. The attempt is made to interpret the found differences. Furthermore it ...
A O Rapp, U Augusta
Accelerated anti-termite laboratory tests, simulation of field conditions and assessment of results for service life
1994 - IRG/WP 94-20034
Termites are one of the most serious biodegrading agents in the tropics. Though some species of termites occur in the warmer temperate regions, only a few species can withstand the rigours of colder regions. Testing of termite resistance of material is done either by field tests or by accelerated laboratory tests. Field tests, though realistic to assess service life, are elaborate, take a long tim...
P K Sen-Sarma
Treatment groups and remedies for CCA treated hardwood and softwood poles
1999 - IRG/WP 99-40142
Different hardwood and softwood species from Bangladesh and Bhutan was investigated regarding density, green fiber stress, natural durability of heartwood and CCA treated sapwood, CCA treatability grades, sapwood thickness, and kiln-drying properties for long term use as electric poles. These properties along with the past service records for nineteen years, separated ten heardwood and five softwo...
A K Lahiry
Present status of using treated wood and private house owner’s expectations in Bangladesh
2004 - IRG/WP 04-30329
In a developing country like Bangladesh more than 80 % of the total population lives in rural areas where building materials are mainly comprised of wood, bamboo, thatch grass, golpata, etc. All these materials, being cellulosic, are easily infected by deteriorating agencies like fungi, termites, beetles etc., as climatic condition of the country is ideal for their thrive. This is a great wastage ...
M A Islam, A K M A Bosunia, S C Ghosh, M O Hannan, A K Lahiry
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
The effects of pH on leaching of copper-chrome-arsenate (CCA) from pressure-treated Kenyan-grown Eucalyptus saligna and Acacia mearnsii: Initial findings.
2002 - IRG/WP 02-30298
The effects of pH on leaching of CCA from pressure-treated Kenyan-grown Eucalyptus saligna and Acacia mearnsii were tested under laboratory conditions. Small samples of the two species (100mm x 30mm x 40mm) were smooth sawn from 8-year old trees to represent equal amounts of both sapwood and heartwood, air-dried to 12% moisture content, end-sealed, and pressure-treated at a commercial treatment p...
R Venkatasamy