Your search resulted in 750 documents. Displaying 25 entries per page.
Some experiences with attack of microorganisms on wooden constructions supporting foundations of houses and bridges
1997 - IRG/WP 97-10232
Reconstructions of bridges and public buildings or damage of houses during the construction of subway lines in Berlin have led to a number of inspections of wooden foundations, mostly pine or spruce piles, representing service lives of between ca. 70 and 140 years. In all cases bacterial attack was found both in wood submerged in ground water and in surface water. The extent of deterioration diffe...
M Grinda
Incorporation of phenyl boronic acid treatment with vapor phase formalization
1997 - IRG/WP 97-40083
Phenylboronic acid (PBA) treatment was incorporated with vapor phase formalization (VPF) in order to increase dimensional stability and boron fixation as well as enhancement of biological resistance. Five and ten hours VPF were applied after PBA treatment as 0.34, 0.50, 1.00 and 2.00% concs. aqueous solutions. Anti swelling efficiency (ASE) attended to 71% in specimens impregnated with 0.50% PBA s...
M K Yalinkilic, S Yusuf, T Yoshimura, W-Y Su, K Tsunoda, M Takahashi
International comparison of three field methods for assessing the in-ground termite resistance of materials - highlights after two years
1999 - IRG/WP 99-20157
First-year results of a comparative study, evaluating the in-ground termite resistance of a range of materials, including CCA and ACQ-treated timbers, using the below-ground exposure, ground contact and graveyard methods against diverse termite faunas were provided in IRG/WP/98-20132. Further annual inspections have confirmed early trends and identified notable differences between sites and method...
M Lenz, J W Creffield, A F Preston, B M Kard, C Vongkaluang, Y Sornnuwat
Improving the weather resistance of glue-laminated jarrah and karri
1994 - IRG/WP 94-40017
Surface modification and dimensional stabilisation significantly increased the dry and wet shear strength of karri and jarrah lap-shear specimens (laminates) bonded with resorcinol formaldehyde. The combination of surface modification (sanding/sodium hydroxide treatment), and furfurylation produced the highest dry and wet shear strengths. Acetylated laminates had the lowest dry bond strength, but ...
J Balfas, P D Evans
Laboratory tests on light organic solvent preservatives for use in Australia. - Part 6: Soft rot resistance of three fully formulated preservatives on different timber substrates
2000 - IRG/WP 00-30245
The above-ground soft rot resistance of substrates treated with three fully formulated light organic solvent preservatives (Cuprivac Green WR, Impresol WR 205 and Vacsol) was studied using a modified vermiculite burial method. The substrates were sapwood of Pinus elliottii and P. radiata and heartwood of Eucalyptus regnans, Pseudotsuga menziesii, Shorea sp. (a lower and a higher density source) an...
G C Johnson, M A Tighe, J D Thornton
Properties of plywood and Oriented Strand Board manufactured with an organic insecticide incorporated in the adhesive formulation
2000 - IRG/WP 00-40174
The efficacy of Fipronil as an insecticide has been established by laboratory and field experiments and commercial use against a broad range of insect pests for various crops. It can be used by either foliar or soil application. Development is underway for the non-agricultural uses of fipronil. Research is ongoing for the control of ants, cockroaches, fleas, ticks, houseflies, mosquitoes, termites...
D P Kamdem, J H Hope, A Jermannaud
Decay and mold resistance of borate modified oriented strandboard
2003 - IRG/WP 03-40260
Decay and mold resistance of zinc borate (ZB) and calcium borate (CB) modified
oriented strandboard (OSB) from southern mixed hardwoods and yellow pine was investigated in this study. Tests were done with brown rot, Gloeophyllum trabeum, and white-rot, Trametes versicolar, fungi for 8 and 12 weeks, respectively. Wood species and fungus type had significant influence on the decay resistance. Decay...
Q Wu, S Lee, J P Jones
The use of modulus of rupture and modulus of elasticity in natural durability testing
1997 - IRG/WP 97-20117
Losses in weight, losses in bending strength and changes in elastic behaviour were assessed in a fungus cellar test with beech wood stakes (Fagus sylvatica). Results were gained after 8, 12, 16 and 20 weeks resp . The outcomes show, that the non-durable species beech is very rapidly attacked by fungi and loses up to 60% of its initial bending strength even within the first 8 weeks. Earlier researc...
L Machek, H Militz, W Gard
Natural exposure weathering tests: Their role in the assessment of wood preservative efficacy
1993 - IRG/WP 93-20006
Previous work has demonstrated the potential and usefulness of natural ageing procedures in e evaluation of wood preservative efficacy. This results from the combination of physico-chemical influences and microbiological interactions with both substrate and wood preservative. In this paper, results are presented for a range of biocide types. Discussions are centred on the value of natural exposure...
G R Williams, J Brown
A new technique for testing decay resistance of framing lumber
2002 - IRG/WP 02-20247
Model house frame units (two studs, top and bottom plates and a central “dwang”) were constructed using short (500-600 mm) lengths of framing timber. Constructed frames were impregnated with water using a mild pressure schedule to raise the initial moisture content to 35-40 % mc. The back face of each unit was then covered with black polyethylene. Two locations at the stud/dwang and stud/botto...
M E Hedley, D Page, B E Patterson
Durability of Wood Plastic Composites Relative to Natural Weathering and Preservative Treatment With Zinc Borate
2005 - IRG/WP 05-40316
Wood-Plastic Composites (WPCs) used for decking have experienced dramatic increases in North America, averaging 25% growth per annum since 1998. A key factor contributing to this growth has been the successfully communicated message that they are "virtually maintenance free". The common perception being that the wood fiber is completely encapsulated by the thermoplastic resin, minimizing the pot...
M E Mankowski, F M Ascherl, M J Manning
The influence of the natural extractives of opepe (Nauclea diderrichii) and African padauk (Pterocarpus soyauxii) timbers on their durability
1996 - IRG/WP 96-30098
Many timbers contain chemical extractives that undoubtedly play a key role in the timber's natural durability. Opepe (Nauclea diderrichii) and padauk (Pterocarpus sp.) are both very durable timbers (class 1), yet they are described as being moderately permeable. This suggests the presence of biocidal chemicals within these timbers, rather than simple blocking agents. Initial trials on the...
E D Suttie, R J Orsler
Improvement of some technological and biological properties of poplar wood by impregnation with aqueous macromolecular compounds
1992 - IRG/WP 92-3721
Poplars (Populus spp) belong to the most important tree species in afforestation programs of the Netherlands. Due to their rapid growth, the wood quality is usually low. Therefore, studies were performed to elucidate whether some technological properties and the resistance against fungal attack could be improved by impregnation with water-soluble resins. The results showed that swelling and shrink...
R D Peek, H Militz, J J Kettenis
Improvement of wood decay resistance by tannin impregnation
1991 - IRG/WP 2380
The fungical effect of tannins is appraised after exposure of treated woods samples to wood rotting fungi. A screening-test is carried out with several solutions containing extracts of two kinds of tannins; a condensed tannin derived from Quebracho heartwood (Schinopsis sp.) and a hydrolyzable one extracted from chestnut heartwood (Castanea sativa Mill). If a fungicidal action was indeed found it ...
D Dirol, A Scalbert
Decrease in the mechanical resistance of blue stained and "orange stained" Pinus radiata wood
1999 - IRG/WP 99-10313
It is recognised that sapwood attacked by Ceratocystis pilifera increases its permeability to pressure preservative treatments. Since hiphae not only utilise pits, but also the cell wall for crossing from one cell to another, the mechanical resistance of the stained wood might be affected. The orange colour very commonly present in Pinus radiata logs heartwood under water sprinklers, has not recei...
M C Rose, L Reyes, J Alvarez, A Andaur, C Beltran, D Rivera
Properties of hot oil treated wood and the possible chemical reactions between wood and soybean oil during heat treatment
2005 - IRG/WP 05-40304
Thermal treatment with hot oil as the heating media based on the original idea from oil-heat treatment in Germany was investigated. The treatment was mainly carried out at 200ºC and 220ºC for 2 hours and 4 hours, and the wood species were mainly spruce and fir. This paper focuses on the difference between soybean oil and palm oil and the possible chemical reactions between wood and soybean oil. ...
Jieying Wang, P A Cooper
Natural Durability of Tropical Species – Variations and Prospects
2005 - IRG/WP 05-10568
The tropical timber resources of the world play an unequivocal role in economic development of both the tropical timber producing and importing regions. This paper describes natural durability as an important and preferred wood quality of tropical species of the world with emphasis on Malaysian hardwoods, the link between various aspects of tropical hardwood durability, hardwood utilization and bi...
A H H Wong, Yoon Soo Kim, A P Singh, Wang Choon Ling
Biological resistance of aldehyde-treated wood
1994 - IRG/WP 94-40018
Biological resistance of wood treated with aldehyde cross-linking agents such as glyoxal, glutaraldehyde and dimethylol dihydroxy ethyleneurea (DMDHEU) were investigated. Sapwood blocks of Japanese cedar and Japanese beech, measuring 20 x 20 x 10 mm³ (T x R x L), were vacuum-impregnated at room temperature with 5-25% of aldehyde solutions. Blocks were kept in the solution for 1 week to gain the o...
S Yusuf, Y Imamura, M Takahashi, K Minato
Soft rot decay of Belian (Eusideroxylon zwageri) wood
1995 - IRG/WP 95-10119
The heartwood of Belian (Eusideroxylon zwageri), an East Malaysian timber species, is naturally durable due to its certain unique anatomical features and high content of extractives. The timber can tolerate years of exposure to hazardous conditions in ground contact and other situations without any significant loss in its strength. A few Belian transmission poles sampled from one locality in Saraw...
A H H Wong, A P Singh
Effect of Scytalidium lignicola on decay resistance and strength of wood
1994 - IRG/WP 94-10061
We reported previously that in laboratory tests, pretreatment of Douglas-fir and Southern Pine blocks with Scytalidium lignicola prevented decay. In the present work, we determined 1) the ability of Scytalidium lignicola to colonize and survive in wood exposed in the field, 2) the decay resistance of blocks removed from previously treated Scytalidium lignicola wood and 3) the effect of Scytalidium...
T L Highley
Preliminary results of the treatment of wood with chlorosilanes
1981 - IRG/WP 3172
It is clear from the initial data reported here that the treatment of pine sapwood with chlorosilanes under the reaction conditions employed did not significantly reduce the decay by both white rot and brown rot fungi. Only the dichlorosilane compounds showed to possess some protective action against fungal attack. Before drawing conclusions on the application of organosilicon compounds as potenti...
M Stevens
Decay resistance of Siberian larch wood against brown rot fungi - Part 2. The effect of genetic variation
1998 - IRG/WP 98-10287
Wood natural decay resistance is mainly restricted in the heartwood part of tree and based on wood microstructure and chemical composition. However, the variation of decay resistant in different wood species is vide and the effect of genotype on decay resistance of Siberian larch wood grown in Finland is not known. The aim of this work was to find out the variation on decay resistance of Siberian ...
H Viitanen, L Paajanen, T Nikkanen, P Velling
A below-ground exposure method for determining the resistance of woody and non-woody materials to attack by subterranean termites
1993 - IRG/WP 93-10012
With existing field test procedures, in which specimens are installed vertically to some of their length into the ground and spaced out from each other ("grave-yard" tests), variations in the rate of contact by termites between replicates can be common. Mechanical damage to specimens during inspection and re-installation may also be difficult to avoid. A new field test method, evaluated in Austral...
M Lenz, J W Creffield
Low polymer levels containing bioactive monomer polymerized in situ provide resistance to Gloeophyllum trabeum
1995 - IRG/WP 95-30066
Wood preservation based on in situ polymerization of potentially bioactive monomers has been studied. Tributyltin oxide acrylate (TBTOA) and pentachlorophenol acrylate (PCPA) were synthesized. Wood samples were treated at 2, 5, 10, 15 and 20% by weight solutions with varying amounts of crosslinker (trimethylolpropane trimethacrylate, TMPTM) and polymerized in situ in wood samples (2.54 x 2.54 x 0....
R E Ibach, R M Rowell
Evaluation of the pulsed-current resistance meter (Shigometer®) for determination of the internal condition of utility poles
1979 - IRG/WP 2128
A number of Telecom poles, which had been removed from service to be replaced by a radio link, were inspected using an electrical resistance meter (Shigometer®). These poles were creosoted, non-durable Victorian species in service in New South Wales. Six of these poles, chosen to represent various internal conditions typical of the range of the population tested, are discussed here. Data, from tr...
J D Thornton, W G Seaman, M McKiterick