Your search resulted in 623 documents. Displaying 25 entries per page.
A non-destructive testing technique for wood poles
1987 - IRG/WP 2293
A method has been developed to evaluate the stiffness and condition of a wood pole based on structural dynamics. This paper describes the results of tests performed on nearly 200 wood utility poles across Western Canada. A high correlation exists between the dynamic non-destructive test and direct mechanical tests. The need for an accurate non-destructive testing technique is demonstrated by the f...
W M Murphy, D E Franklin, R A Palylyk
A novel method for evaluating the performance of water repellents
1987 - IRG/WP 2279
Application of water repellent formulations to timber surfaces offers protection from the weather, reducing degrade and movement. A novel test method has been developed to evaluate the comparative efficacy of such formulations when samples are exposed to weather. The method uses sapstain free sapwood of defect free, untreated, seasoned Radiata pine, (Pinus radiata D. Don.) Water Repellency was det...
A R Moffat
Sub-group on Basidiomycete tests: Experimental programme and schedule of participants
1980 - IRG/WP 2145
The objectives of this IRG COLLABORATIVE BASIDIOMYCETE TEST are to compare results and assess reproducibility of a miniaturised wood block toxicity test when undertaken by different workers in different laboratories. The co-operative scientists and institutes are: Dr K Messner from Vienna (Austria); Dr R S Smith from Forintek (Canada); Mr J Hansen from Sadolins (Denmark); Mr B Jensen from Gori (De...
A F Bravery
Soft rot in heartwood of preservative-treated pole stubs of Eucalyptus cypellocarpa L. Johnson
1983 - IRG/WP 1204
Pole stubs of Eucalyptus cypellocarpa L. Johnson, treated in the sapwood with certain waterborne preservatives and exposed for 21 to 23 years in a dry tropical region were severely soft-rotted in the heartwood, as well as the sapwood. They broke with a brash fracture when stress tested (loaded as a cantilever) in the field. The severe soft rot in the heartwood was not detected by the knife test or...
J E Barnacle, G C Johnson, M A Tighe
A novel technique for comparative toxicity studies of potential insecticidal wood preservatives
1983 - IRG/WP 2198
For some years now a device has been under development at the New Zealand Forest Research Institute, the purpose of which is to study the effects of sub-lethal amounts of stomach poisons (but also of fumigants and contact active materials) on the co-ordinative abilities of a cerambycid larva. This insect is Prionoplus reticularis - indigenous to New Zealand its larvae feed in decaying logs and are...
D J Cross
A combined method for drying and preserving wood in a single step process
2000 - IRG/WP 00-40183
Based on a convective dryer, this process allows to dry and treat wood blocks with diffusible preservatives in the same time. A boric acid solution (heated to fix the wet temperature of the system) is pumped and introduced in the flow system through a venturi, where the air coming back from the drying cell also arrives. The role of the venturi is to create a dispersion of boric acid solution micro...
O Colin, C Dupuis, E Mougel, A Zoulalian, M-F Thévenon
The critical timing of inspections for field testing of natural durability
1994 - IRG/WP 94-20018
An overestimation of performance will almost always result if the condition of a specimen is considered to be attained at the precise time that an inspection is carried out. The time at which the condition is actually attained, referred to in this document as the "Condition time", is best considered to be halfway between two successive inspections. The requirement to obtain data that is relevant t...
J D Thornton
Leachability of active ingredients from some CCA treated and creosoted poles in service. A progress report after 10 years testing
1990 - IRG/WP 3627
CCA K33 TYPE B treated or creosoted poles, 10 pieces of each treatment type, have been monitored from the treatment plant to an electricity line, which was build up in Southern Finland in 1978. Preservative retention was determined by taking borings at four different levels: 1.5 m from the top end, 1 m above ground line, ground line and 0.5 m below ground. Determinations were made before setting u...
A J Nurmi
Leaching from field test stakes. Results from two different methods of analysis
1993 - IRG/WP 93-50013
Field test stakes treated with Boliden K33 containing copper, chromium and arsenic exposed at three different fields in Sweden and rejected due to decay, have in two studies been analysed regarding leaching and remaining preservatives. The stakes have been exposed during 20 to 43 years. The density of the stakes and content of copper, chromium and arsenic have been determined in the top part of th...
F G Evans, M-L Edlund
Acoustic technique for assessing decay in preservative treated wood
1998 - IRG/WP 98-20138
This study investigated the suitability of vibration techniques to assess the performance of wood preservatives in ground contact. Small stakes (10 x 5 x 100 mm3) of treated and untreated Scots pine sapwood were exposed to decay in lab-scale terrestrial ecosystems. Tests were conducted using three different soils including a garden compost soil, and soils obtained from a test field and a conifer f...
L Machek, M-L Edlund, R Sierra-Alvarez, H Millitz
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
Influence of the nature of the substrate and the method of inoculation on the degradative activity of soft rot fungi
1998 - IRG/WP 98-20133
The European Standard (ENV-807) determines the threshold of effectiveness of wood preservatives against the action of soft rot Ascomycetes fungi. Its application in the treatment of wood used in the hazard class 4 does not always offer repeatable results, which could be expected in an experimental norm.
For this reason, in this paper, we have evaluated the diverse variables that might influence t...
M T De Troya, A M Navarrete, F Rubio, J Jiménez, D Muñoz-Mingarro, C Rodríguez-Borrajo, F Llinares, M Yuste
Effects of the delay in the beginning of treatment on absorption and distribution of water-soluble salts in posts treated by sap-replacement method
1992 - IRG/WP 92-3719
One of the most important matters in green wood treatments, such as sap-replacement method, is knowing the longest time available for beginning treatment without losing efficacy. In this paper, the influence of this factor on absorptions and distribution of the preservative into the wood is analized. Tree start-up times were first chosen: 3-6 hours, 48 h and 120 h after being cut down. The treatme...
M V Baonza Merino
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
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
Estimating the size of subterranean termite colonies by a release-recapture technique
1980 - IRG/WP 1112
The technique is described and the results of an exploratory field trial are presented. The colony size estimate from weekly termite collections varied considerably, but nevertheless permitted assigning termites at three locations to three categories of greatly different colony size. The sizes of the three estimates were much greater than anticipated and included a multimillion termite complex of ...
G R Esenther
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
Some Experiences with Stake Tests at BAM Test Fields and in the BAM Fungus Cellar
Part 1: Comparison of Results of Visual Assessments and Determinations of Static Moduli of Elasticity (MOE)
2005 - IRG/WP 05-20319
With examples of routine in-ground stake tests differences are shown in the performance of wood preservatives at the BAM test fields Lehre and Horstwalde and in the BAM fungus cellar. Signs of attack of micro-organisms were assessed visually according to EN 252. Periodical determinations of static moduli of elasticity (MOE) revealed the influence of the attack on the elastic properties of the wood...
M Grinda, S Göller
The results of detection on CCA components of the soils contacted with CCA-treated woods - A trial study for the availability of the burial Method as a disposal CCA treated wood waste
1993 - IRG/WP 93-50005
The objecteve of this experiment is to get a knowledge that, when CCA treated wood wastes were buried in a soil as a disposal, the soil would be or not be contaminated by the components of CCA preservatives in wood wastes. The specimens used were cutting logs and chips made of the CCA treated electric pole waste. The soil was buried to the 15 cm depth and the log specimens were set in the soil for...
K Suzuki, H Sonobe
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
The “wire-loop slicing technique” for the rapid field collection of large numbers of Coptotermes acinaciformis termites from above-ground mound colonies
2006 - IRG/WP 06-10583
This technique of rapidly slicing through an above-ground C. acinaciformis mound colony with a steel wire-loop attached to a vehicle allows the collection of large numbers of termites. The sliced mound topples onto a tarpaulin arranged on the ground, the outer wall layers break away in large segments, and the carton materials incorporating the termites are readily collected and transferred to larg...
B M Ahmed, J R J French
High-energy multiple impact (HEMI)-test – Part 2: A mechanical test for the detection of fungal decay
2006 - IRG/WP 06-20339
The suitability of the high-energy multiple impact (HEMI)-test for detection of early fungal decay was examined. The HEMI – test characterizes the treatment quality of thermally modified wood by stressing the treated material by thousands of impacts of pounding steel balls. This method differentiates between heat treatment intensities, which are expressed by structural changes of the wood. Simil...
C R Welzbacher, C Brischke, A O Rapp
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