Your search resulted in 1408 documents. Displaying 25 entries per page.
The attack of naturally durable and creosote treated timbers by Limnoria tripunctata Menzies
1995 - IRG/WP 95-10132
Limnoria tripunctata was found tunnelling in creosote treated Douglas fir (Pseudotsuga menziesii) pilings and naturally durable greenheart (Ocotea rodiaei) gate seals at two sites on the south coast of the United Kingdom. Examination of thc creosote-treated wood showed that Limnoria tunnels were concentrated at a depth of 2-3 cm from the timber surface, where creosote loading was lower. Fewer tunn...
A J Pitman, G S Sawyer, G F Daniel
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
Polyflavonoid tannins - From a cause of CCA soft-rot failure to the "missing link" between lignin and microdistribution theories
1986 - IRG/WP 3359
Polyflavonoid tannins are proven to be fast-reacting with CCA solutions and hence, to be strong competitors of the structural wood constituents for fixation of CCA preservatives. The consequence of this effect is that even relatively small amounts of tannin cause severe undertreatment of the structural wood constituents which in turn badly affects the long term durability of CCA-treated timber. Th...
A Pizzi, W E Conradie, M Bariska
Laboratory determination of the natural decay resistance of some lesser-utilized timbers from Tanzania against wood decay fungi
2004 - IRG/WP 04-10517
Four lesser known/utilized timber species (sap and heartwoods) from Tanzania, namely Albizia lebbeck, Zanthoxylum gilletii, Faurea saligna and Parinari curatellifolia were exposed to the brown rot fungi (Gloeophyllum trabeum and Coniophora puteana) and the white rot fungus (Coriolus versicolor) to determine their natural decay resistance according to the EN 113 standard procedure. The timbers were...
P R Gillah, R C Ishengoma, E Julias, S A Amartey, D H Kitojo
Fluoride woodpill
1987 - IRG/WP 3431
Decay problems of spruce joinery in the Netherlands in the 1960's and 1970's led to the introduction of preservative treatment. Because of the known penetration difficulties with Spruce, the results of the treatments were not always successful. The fact that the decay was found only in the joints led to development of the philosophy of "local preservation" of the joints in remedi...
J W P T Van der Drift, K J M Bonsen
Comparison of decay rates of preservative-treated stakes in field and fungus cellar tests. Results after 40 months fungal cellar exposure
1983 - IRG/WP 2200
Decay rates of preservative-treated Pinus radiata stakes during 40 months exposure in the FRI fungus cellar were compared with those of similarly treated material in a field test. Decay rates in the fungus cellar were from 4 to 100 times higher than in the field, although for the majority of preservatives the rate was between 7 and 12 times higher. The lag phase before onset of decay, noticeable w...
M E Hedley
Effects of boron treatments on partially decayed oak and pitch pine heartwood
1996 - IRG/WP 96-30106
This paper reports results of borate based preservative treatment and leaching experiments on partially decayed oak and pitch pine heartwood. Previous experiments have shown little damage is caused to sound timber of these types when treated with Polybor and Boracol 20 preservatives. This experiment was carried out to assess the suitability of selected borate based preservatives for use in histori...
S McCutcheon, G M Smith, J W Palfreyman, P Durrant
Soft rot fungi as possible sources of odor in impregnated wood in buildings
1993 - IRG/WP 93-20013
Wood preservatives are frequently used inside houses. In several cases impregnated wood, particularly when used in crawlspaces or other near-ground constructions, has been found to be a source of odor. Mold fungi, soft rot fungi actinomycetes or bacteria growing on impregnated wood are possible producers of the odor. Analyses of volatile emissions from impregnated wood with odor and pure cultures ...
J Bjurman, J Kristensson
Modelling the control of decay in freshly felled pine poles
1997 - IRG/WP 97-10206
In a recent study investigating control of decay in freshly felled pine utility poles, it became apparent that the efficacy of different treatment methods was strongly related to the size of the material being treated. A topical application of 5% w/v disodium octaborate tetrahydrate (DOT), brush applied to the cut surfaces of logs with otherwise intact bark was just as effective at excluding white...
M W Schoeman, W Van der Werf, J F Webber, D J Dickinson
Ultrastructure of degraded, CCA-treated Pinus radiata wood from a marine pile
1990 - IRG/WP 1461
During an inspection of marine piles, 12 years after installation, severe degradation was noted on one of them in the vicinity of a corroded eye-bolt. The wood was dark brown in colour and tended to crumble easily. Wood fragments were examined by light microscopy and scanning and transmission electron microscopy and were also analysed for carbohydrates and lignin. Light microscopy showed numerous ...
A P Singh, M E Hedley
Investigation of microwave as a means of eradicating dry rot attack in buildings
1992 - IRG/WP 92-1545
A microwave-apparatus developed for treatment of building-structures infested by dry rot was tested in the laboratory. The test-conditions simulated treatment of either infested timber or infested brickwork. Sawdust samples, both wet and dry, infested by viable mycelium of Serpula lacrymans were packed in glass-tubes. The tubes were then placed in the middle of either 20 cm thick wooden beams or 3...
C Kjerulf-Jensen, A P Koch
Movement and persistence of Dazomet and pellected methylisothiocyanate in wrapped Douglas fir and southern pine timbers
1991 - IRG/WP 1496
The movement and persistence of Dazomet (tetrahydro-3,5-dimethyl-2 H-1,3,5 thiadiazine-6-thione) and pelleted methylisothiocyanate (MIT) was evaluated in wrapped Douglas-fir and Southern Pine timbers. MIT pellets did not impart a fungistatic effect to any of the timbers. Failure of MIT was probably due to loss of MIT from pellets prior to application. Fungistatic effect of Dazomet was consistently...
T L Highley
Development on Damage Functions of Wood Decay for Building Envelope Design
2005 - IRG/WP 05-10556
For the hygrothermal analyses of building envelope systems for insulation design, we tried a natural decay test of wetted wood specimens without any inoculation of fungi. Three principal experimental types: under steady-state conditions (Experiment A), at a cyclic water dripping under Non-steady conditions (Experiment B) and at a cyclic water dipping under-steady conditions (Experiment C), were ca...
H Suzuki, Y Kitadani, K Suzuki, A Iwamae, H Nagai
A Soil Bed Test of the Effect of CCA Penetration on the Performance of Hem-fir Plywood
2004 - IRG/WP 04-30332
An accelerated decay test was set up to compare the performance of CCA-treated Western hemlock/amabilis fir plywood treated to meet the preserved wood foundation (PWF) retention standard with various patterns of preservative penetration. Short lengths of treated plywood and comparable untreated material were installed in a soil bed. After eleven years of exposure, the CCA treatments were all sou...
P I Morris, J K Ingram
Long-term protection of stored lumber against mould, stain, and specifically decay: A comparative field test of fungicidal formulations
1984 - IRG/WP 3281
The problem of decay in packaged, unseasoned lumber stored for many months has become of major importance in recent years. Large financial claims have resulted from decay in Canadian lumber stored at length in seaports and storage yards of distributors. For decades acceptable protection from moulds and sapstain was readily achieved with chlorinated phenols applied at appropriate treating levels. H...
A J Cserjesi, A Byrne, E L Johnson
The evaluation of the occurrence of soft rot in creosoted wooden poles
1988 - IRG/WP 1368
The occurrence of soft rot decay in creosoted wooden poles for overhead power lines was investigated by collection of field samples, their subsequent microscopic examination and statistical analysis of the data collected. Examination of samples collected from 296 poles revealed that approximately 15% of the pole population studied (Eastern Electricity Board) showed the presence of soft rot decay. ...
A Wylde, D J Dickinson
Kinetic of the wood degradation produced by wood decay fung
1993 - IRG/WP 93-20016
The degradation degree of a wooden structure has a direct influence on its loss of mechanical strength. It's necessary to deepen in non destructive techniques which permit to extrapolate the results obtained in laboratory to structural timber used in the building's construction. This work studies the relationship existing between the pulse velocity of ultrasonic waves and the wei...
M T De Troya, A M Navarrete, A Sanchez, V Bucur
Bending creep test of plywoods under long term exposure to fungal attack
1981 - IRG/WP 2163
Bending creep test and decay test were coupled in order to evaluate the durability of structural plywoods and preservative efficacy. Experimental blocks, 5.0 x 1.2 cm² section x 35.0 cm length, were impregnated with distilled water and inoculated with mycelial fragments of test fungus. Polyethylene bags stretched with metal frame were used as decay chambers. The chambers containing inoculated blo...
M Takahashi
Premature decay of CCA-treated pine posts in horticultural soils - An overview
1984 - IRG/WP 1241
The recent discovery in New Zealand of early decay in CCA-treated pine posts set in horticultural soils led to the establishment of a comprehensive research programme. The objectives and outline of this programme are presented together with an overview of research progress to date. Results suggest that premature decay of CCA-treated timber is restricted to material placed in highly cultivated soil...
J A Butcher
Oxalate production and calcium oxalate accumulation by Gloeophyllum trabeum in buffered cultures
1994 - IRG/WP 94-10075
Most basidiomycetous fungi produce oxalic acid as a result of their metabolic activities and nutrient procurement. There is currently a renewed interest in the role that oxalic acid may play in the decomposition of wood by basidiomycete fungi. It has been observed that although most wood degrading fungi have the capacity to produce oxalic acid, not all of these organisms express this capacity equa...
J H Connolly, J Jellison
High CCA retentions and the protection of eucalypt power poles
1983 - IRG/WP 3226
Tasmanian power pole material treated to high retentions, was analysed to accurately determine the amount of CCA preservative in the timber. Material from the same disc was subsequently exposed in unsterile soil in order to determine the effectiveness of treatment. Results showed that even at high retention levels, soft-rot attack was not prevented. Fourteen further poles were sampled, but this ti...
L E Leightley, J Norton
Soft rot tests
1983 - IRG/WP 2206
At the IRG meeting in Turkey it was proposed that developments in testing preservative-treated wood in unsterile soil according to techniques variously described as "fungus cellar", "soil-bed", or "accelerated field simulation" be considered along with conventional laboratory procedures as the basis for a standard test. Before formulating any co-operative test programme it is essential to examine ...
J A Butcher
The influence of gaseous oxygen concentration on fungal growth rates, biomass production and wood decay
1998 - IRG/WP 98-10283
The effects of air and several levels of oxygen balanced with nitrogen (% oxygen (v/v) nitrogen to 100%) on growth rates, biomass production and wood decay were investigated. The best technique for measuring daily growth rates in anaerobic jars was found to be by using 40 mm petri dishes which were attached to the walls of the jars. At the end of the test period the same petri dishes were also use...
S M Kazemi, D J Dickinson, R J Murphy
Biocontrol and bioprotection of wood decay and sapstain fungi
2003 - IRG/WP 03-10474
The most serious damages caused in the wood industries by decay and sapstain fungi, and the growing international pressures on the use of biocides products with toxic active ingredients harmful to human health and the environment, have made it necessary to search for alternative chemical products to protect the wood, and for the possibility to use micro-organisms as biological controllers. This la...
M T De Troya, F Rubio, M Villarreal, F Arenal, F Llinares, V Rubio, D Muñoz-Mingarro, N Acero
Summarized comparison of four techniques for detecting defects in poles
1979 - IRG/WP 2126
Since our discussions in open session of Working Group II at Peebles, a number of workers in Australia have collaborated in comparing the efficacy of X-ray, sonic testing, or resistivity measurements for detecting internal defects in poles. The purpose of this circular is to draw to your attention some of the results, in summary form. No attempt has been made to compare techniques. More detailed a...
H Greaves