Your search resulted in 263 documents. Displaying 25 entries per page.
Field test design for service life prediction of wooden components
2005 - IRG/WP 05-20308
Wood is predominantly degraded by organisms. Thus, compared to other building materials, service life of wooden material is influenced by many more factors, which are divided into direct and indirect factors. Climate, geographical position, and construction criteria count to the indirect decay factors. Besides material inherent properties (natural durability, wood preservatives), wood temperature...
A O Rapp, C Brischke
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...
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 ...
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...
Minimisation of the Environmental Impacts of Coatings on Exterior Wood by Optimisation of their Life Spans
2003 - IRG/WP 03-50197
The study has shown that the environmental impacts from coatings on exterior wood are dependent criteria on their life spans. A minimisation of the environmental impacts can be performed with the help of the integrated design model, which is tested in this study. The optimal life spans, found as reference service lives from the exposure tests, statistical evaluation and the assessment of experts w...
Social and economocal impact of an extension of service life resulting of an adequate preventive treatment. Application to wooden components used in urban areas with a high density of population
1993 - IRG/WP 93-50001-15
Le document évalue les problèmes rencontrés en zone urbaine pour le sauvetage des constructions: coordination de la lutte, délimination des chantieres et des périmètres d'investigation, nuisances causées par les interventions, risques pour la santé, risques pour l'environnement. Coûts. Comparaison socio-économique du traitement préventif et des interventions à posteri...
A T De Lelis, G A C Lopez
L-joint based testing for service life prediction of exterior plywood in out of ground contact conditions
2006 - IRG/WP 06-20342
Good biological performance of several plywood types in exterior conditions is most probably related to altered wood moisture behaviour compared to solid wood. Therefore a test set up was developed, using EN 330 L-joint testing methodology, to facilitate differentiation of plywood for exterior applications. The proposed test set up is an adaptation of an accelerated L-joint method introduced by V...
J De Smet, I De Windt, J Van Acker
How to win friends and influence the market — Service Life Prediction and performance-based durability assessments of wood products in construction
2006 - IRG/WP 06-20348
Due to direct and implied demands from the market and from e.g. the EU Construction Products Directive, the need to supply service life estimates for building products is growing. For several years, a development of Service Life Prediction (SLP) methodologies has been going on, but the awareness of this development has hitherto reached only a very limited extent in the wood sector. For materials w...
A roadmap for performance-based specification of wooden components based on service life prediction
2007 - IRG/WP 07-20351
The need for an unified and harmonised system for performance classification and specification of wood and wood-based products in Europe emanates from requirements of users and the European Construction Products Directive, CPD. A road to a feasible specification system is outlined. Exposure-related performance prediction was worked out as a key task on the way to product specification. Therefore s...
C Brischke, A O Rapp
Service life prediction of plywood
2007 - IRG/WP 07-20367
Plywood is the wood based panel showing the best physical and mechanical properties for application under moist construction conditions. Appropriate physico-mechanical durability for exterior applications in transportation or construction systems can be guaranteed by assessment of the glue bond quality and mechanical characteristics. However, due to the fact that mainly non-durable wood species ar...
J Van Acker, J De Smet
Predicting the decay resistance of timber above-ground: 2. When can reliable field data be obtained?
2007 - IRG/WP 07-20368
Application of modern performance-based engineering and design requires building products that are thoroughly characterised in terms of their ability to perform as expected over time. The engineering community is attempting to use this information to provide predicted service-lives for various building elements. Increasingly, this service-life prediction must be based on objective measurement coup...
L P Francis, A J Swain, J J Morrell
Expected service life of outdoor wooden structures such as guard fences and noise barriers indicated by questionnaire survey
2007 - IRG/WP 07-20372
Forestry Agency, Japan has intended to expand the utilization of domestic wood in many areas such as not only housing constructions also outdoor structures. In order to respond the policy, actual durability and service life of these structures should be clarified, and the guide line for archiving planned service life also should be established. Japan Wood Preservers Industries Association carried ...
K Yamamoto, A Makita, A Yamaguchi, T Shiraishi, K Maeda, D Tezuka, S Katsumata, M Higaki
Tropical In-Ground Durability of CCB-treated Keruing and other Structural Sarawak Timbers after 8 – 10 Years Exposure
2007 - IRG/WP 07-30439
The heartwood of 12 mainly low-durability native timber species of Sarawak [4 Dipterocarpus (Keruing) species, Anisoptera grossivenia (Mersawa kunyit), Canarium apertum (Seladah), Dacryodes incurvata (Seladah laut), Dryobalanops oblongifolia (Kapur kelansau), Mesua macrantha (Mergasing), Podocarpus micropedunculatus (Kayu cina), Shorea compressa (Engkabang langgai), and Pterospermum javanicum (Ba...
A H H Wong, Ling Wang Choon
In-service performance of wood depends upon the critical in-situ conditions. Case studies.
2008 - IRG/WP 08-20382
Wood is a unique building material, but is by nature designed to deteriorate. A detailed understanding of the factors and interactions involved are important when working with service life prediction of wooden components in buildings. Wood may experience exponential fungal degradation caused by variation in the climatic factors within a small limited area and by minor imperfection in the wooden ...
L Ross Gobakken, J Mattsson, G Alfredsen
Service life prediction of wood: scale-dependent tools within a bio-engineering framework
2008 - IRG/WP 08-20387
Service life prediction (SLP) is a complex yet essential method for the building industry. Accurate and precise assessment of the components is crucial for a strong position of wood on the market. As it is a biological material, wood has an inherent variability and is susceptible to fungal attack. Therefore a profound knowledge of these characteristics is the corner stone of SLP for wood products....
J Van den Bulcke, J Van Acker, M Stevens