Your search resulted in 567 documents. Displaying 25 entries per page.
Multiple-Phase Pressure (MPP) Process: One-stage CCA treatment and accelerated fixation process. 3. Effect of process variables on sapwood treatment and CCA fixation.
1998 - IRG/WP 98-40114
The Multiple-Phase Pressure (MPP) Process achieves treatment and fixation as combined process using hot CCA, within a 2-3 hour time-frame. Timber is treated to saturation with hot CCA using an empty cell process. During the pneumatic pressure phase, hot solution is held in the wood in an otherwise liquid-free treatment vessel until fixation is >95% complete.
This report details a factorial des...
H Pearson, K Nasheri, J A Drysdale, G Durbin, M E Hedley
Comparative study on the leaching of wood preservatives between natural exposure and accelerating laboratory conditions
1999 - IRG/WP 99-50134
Impregnated specimens with CCA, ACQ, and BAAC were subjected to leaching tests. Specimens of 2x2x1 cm3 in size were used for the laboratory leaching test for 10 days according to JIS K 1571. Specimens of 25x1 x1 cm3 were used for outdoor leaching test for 6 months. Total leaching amounts of boron per cm3 of specimens treated with BAAC were 325 µg in the laboratory test and 206 µg in the outdoor ...
K Yamamoto, S Motegi, A Inai
Inhibition of the biodegradation of coniferous and broadleaved wood by new imidazolium salts
2003 - IRG/WP 03-30320
Studies were carried out on fungicidal values of fourteen potential wood preservatives – modified quaternary heteroaromatic compounds using the screening agar-block. The vacuum treated blocks (22mm x 17mm x 12mm) of Scots pine (Pinus sylvestris L.), spruce (Picea excelsa L.), beech (Fagus silvatica L.) and birch (Betula verrucosa Ehrh.) with testing compounds were exposed to Coniophota puteana a...
J Zabielska-Matejuk, J Pernak, W Wieczorek
Implications for comparability of laboratory experiments revealed in studies on the effects of population density on the vigour in groups of Coptotermes lacteus (Froggatt) and Nasutitermes exitiosus(Hill) (Isoptera: Rhinotermitidae, Termitidae)
1983 - IRG/WP 1197
(Summary of paper 1194)
The vigour - survival and wood consumption - of groups of Coptotermes lacteus and Nasutitermes exitiosus was measured when termites were kept at different population densities (g termites/ mL) by changing group size and/or volume of the holding container. A characteristic pattern emerged. At low population densities (< 0,01 g/mL) performance of termites improved with an increase in group size; at higher population densities it tended to decline. The impact of altering group size and container volume on termite vigour was most pronounced at low densities; at higher population densities, performance tended to be more stable but declined markedly when termites became overcrowded. In most jar-type experiments on termites, especially those conducted in Europe and the U.S.A., small groups of termites are housed in disproportionately large jars, resulting in very low, sub-optimal population densities. Suggestions are made for improvements in experimental design that would lead to an enhancement of the comparability of results from different laboratories.
M Lenz, R A Barrett, E R Williams
Detection of termite attack in wood using acoustic emission
1989 - IRG/WP 2331
Acoustic emission (AE) is the elastic wave produced by the strain energy released in the process of fracture of a material and propagates through it. The object of this report is to detect AEs produced by the termite activities and to evaluate the possibility of using an AE monitoring test to nondestructively detect the termite attack in wood. It was revealed that AEs were detected from the specim...
Y Fujii, M Noguchi, Y Imamura, M Tokoro
Blue stain in timber in service. Progress review of Sub-group collaborative tests - 1981/82
1982 - IRG/WP 2178
Following from the discussions after reporting Document IRG/WP/2146 at the Meeting in Sarajevo, 1981, it was decided that 1.) more precise definition was needed of the artificial weathering schedules used in the work - participants to re-check Table 8 and send further details or amendments to Dr Bravery; 2.) a further test employing a wider range of chemicals was necessary using a smaller range of...
A F Bravery, D J Dickinson
Hole delimination inside round timber via ultrasonic techniques
1990 - IRG/WP 2358
A fast and economic circular scanning method to localize and evaluate holes inside round timber is presented. This method consists in measuring transit times of the ultrasonic wave by fixing the transmitter probe in the perimeter of the sample, then moving the receiver probe every ten degrees until completion of the circle. The scanning is done with a cheap and light instrument. Tests are made wit...
G Prieto, A Fernández Cancio
Variation in field test performance of untreated and CCA-treated lesser-known Surinamese wood species
2000 - IRG/WP 00-20213
In Suriname three different field test sites have been used to verify the biological durability of CCA-treated wood and a range of wood species including lesser-known and lesser-used wood species. In total 37 tropical wood species were tested untreated and for 17 of the less durable species CCA-treatments were included as well. Although the three sites are located in the tropical region they diffe...
J Van Acker, M Stevens, L Comvalius
Predicting the decay resistance of timber above-ground: 1. Climate effects
2006 - IRG/WP 06-20330
Despite the benefits of using timber as a building product, it is disadvantaged by current Australian Standard durability classifications which lack the sensitivity desired by engineers and architects. To address the need for more sensitive timber service-life information in Australia, an above-ground durability research program was established in 1987. One focus of research is the relationship be...
L P Francis, J Norton
Effects of chlorothalonil (CTN) and butylated hydroxytoluene (BHT) on microbial communities involved in the deterioration of wood using T-RFLP I: Accelerated laboratory decay study
2006 - IRG/WP 06-20332
The effects of Chlorothalonil (CTN) and Butylated Hydroxy Toluene (BHT) on microbial species diversity in wood and the surrounding soil are being assessed by Terminal Restriction Fragment Length Polymorphism (T-RFLP). CTN was selected as a trial organic wood preservative, and BHT is being evaluated for its synergistic effects with CTN. Results from an accelerated decay test will be presented. The...
G T Kirker, M L Prewitt, S V Diehl
Effect of wood decay on the proportional limit of thin wood samples stressed in the bending mode
2006 - IRG/WP 06-20334
When using bending stiffness as a measure of wood decay it is advantageous to repeatedly test individual samples after they are exposed to decay fungi for varying periods of time. In order to obtain reliable results, variation in modulus of elasticity (MOE) values of the test samples that are repeatable bent to a given deflection must be considered. In this study it was shown that sound 3mm thick ...
G Li, D Nicholas, T Schultz
Testing durability of treated wood according to EN 252. Interpretation of data from Nordic test fields
2006 - IRG/WP 06-20341
To evaluate the effectiveness of new wood preservatives intended for treated wood in ground use there is a European standard, EN 252. The test shall run for five years before any formal interpretation of the results can be made.
Due to environmental concerns, the use of wood preservatives based on copper, chromium and arsenic (CCA) has been restricted in recent years. As a consequence of restrict...
M L Edlund, F G Evans, K Henriksen, T Nilsson
Testing biological durability of wood-plastic composites
2006 - IRG/WP 06-20347
Testing biological durability is inherently different for wood-plastic composites (WPC) compared to solid timber. However there is clearly a need for more information on the durability of WPC’s, on the effect of decay on the material properties of WPC’s and on methods for assessing decay of WPC’s. For the emerging European WPC market there has been some discussions on how to work on these to...
J Van Acker
Standard Test Methods for Wood Preservatives by Laboratory Agar-Block Test
2006 - IRG/WP 06-20350
Wood is one of the most valuable and versatile resources for all sorts of constructional purposes. But timber in its various forms is subjected to several types of deterioration. This standard lays down the method for the laboratory determination of threshold value of wood preservatives against fungi. Most chemicals are initially tested for their ability to control decay fungi in agar-block tests....
P K Sarker, M A Rahman, M R Bulbul, T Das, G N M Ilias
Resistance of DMDHEU-treated pine wood against termite and fungi attack in field testing according to EN 252. Results after 30 months
2006 - IRG/WP 06-40354
The aim of this study was to determine the effectiveness against decay and termite attack of pine sapwood treated with pure and modified DMDHEU in a field test according to European Standard EN 252. Some of the treatments tested were able to increase, within the period of the test reported (30 months), the resistance of the wood both to micro-organisms and termites. The curing process seems to be ...
S Schaffert, L Nunes, A Krause, H Militz
Accelerated assessment tests of new termiticides
2007 - IRG/WP 07-20353
One of the biological agents, which cause major damage to wood in Spain, is the subterranean termites.
The systems used for controlling termites don’t eradicate them, and the products presently used to treat wood against them, due to their toxicity and their persistence in the environment, could be prohibited in the near future in Europe as consequence of the 98/8/EC Directive (usually called t...
M T Troya, M J Prieto, D Lorenzo, F Rubio
Current state of world standardization in the toxicometric methods for testing of wood preservatives
2007 - IRG/WP 07-20354
The paper presents an outline of the history of forming standardized toxicometric methods for testing of wood preservatives in the world during last 100 years. Numerous studies resulted in three main methods which are currently used for official and basis assessment of biocides:
- agar-block method in Europe (EN 113);
- soil-block method in the USA and Pacific countries (ASTM D 1413);
- modifi...
J Wazny
Lyctine susceptibility testing and dealing with rarely susceptible hardwood species
2007 - IRG/WP 07-10607
This study examined the lyctine susceptibility of 16 timber species or hybrids. Several of the timbers have been placed previously in a ‘rarely susceptible’ category, but for standards and compliance purposes, such in-between ratings are not acceptable. Timber specimens were spot tested for starch content, and exposed to three species of lyctine beetles in an insectary. New criteria were devel...
L J Cookson, J Carr, N Chew, J W Creffield
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
Growth and succession of mould on commercial paint systems in two field sites
2007 - IRG/WP 07-30421
Discolouring fungi reduce the service life of coated wooden claddings in façades and increase the total cost of ownership due to shorter maintenance intervals. It is of major importance to find paint systems for wood which are durable and have a high resistance to mould growth. A total of 15 paint systems from 9 different manufacturers were exposed on two field sites, Sørkedalen and Birkenes, ...
L Ross Gobakken, K M Jenssen
Electrokinetic Accelerated Ingress of Boron After Surface Treatment of Wood
2007 - IRG/WP 07-40372
In this work electrokinetic acceleration of boron penetration after surface treatment is proposed in order to offer an alternative to the often low penetration rates based on diffusion. Electrodialytic experiments showed that boric acid could be transported as negatively charged complexes with tartaric acid in aqueous solutions at pH 4-5. Boric acid could not be transported when tartaric acid was ...
I V Christensen
Durability of some alternatives to preservative-treated wood. Progress report 2: Results from field tests after 5 years’exposure
2007 - IRG/WP 07-30442
A number of alternatives to preservative-treated wood have been tested according to EN 252 (stake test) and a specially designed ground-proximity field test, the latter in Sweden as well as in Hawaii, USA. Seven untreated wood species and four alternative wood treatments labelled as environmentally friendly (acetylation, linseed oil, heat treatment, vinyl polymer) were included in the study. Four ...
M-L Edlund, J Jermer
Field Liners as physical barriers to prevent wooden utility pole decay in soil: An accelerated field simulation trial
2008 - IRG/WP 08-20384
Field Liners (FL’s), plastic sleeves used to protect in-ground wooden poles from fungal and termite damage, have been tested before as physical barriers to prevent contact between soil and wood and to retain wood preservative treatment. These earlier studies concentrated mostly on creosote preserved poles and early generation FL’s which were cumbersome in their application. The newer generatio...
A R Howgrave-Graham, L J Cookson, T Hale
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
Accelerated fixation of ACQ-D treated Chinese fir with different post-treatments
2008 - IRG/WP 08-40400
With the enhanced focus on the environmental impact of the preservative-treated wood in recent years, it is necessary to perform some post treatments to prevent contamination of soil and ground water and reduce copper losses from ACQ treated wood in service. In this study, the potential of hot air, hot water, steaming and microwave post treatments to accelerate the fixation of copper in ACQ-D trea...
Lili Yu, Jinzhen Cao, P A Cooper