Your search resulted in 681 documents. Displaying 25 entries per page.
Improvements of monitoring the effects of soil organisms on wood in fungal cellar tests
1996 - IRG/WP 96-20093
Accelerated testing the durability of preservative treated timber in a so called "fungal cellar" or "soil-bed" to evaluate its performance in ground contact is widespread practice. In order to obtain a more accurate and reproducible estimate of preservative performance, several institutes, among them the BAM in Berlin, have routinely carried out static bending tests in addition to visual examinati...
I Stephan, S Göller, D Rudolph
The performance of wood preservatives in soil-bed soft rot tests
1993 - IRG/WP 93-20007
Testing the efficacy of wood preservatives in soil is recognised as a fundamental part of the assessment of long-term wood protection in ground contact. Laboratory based tests can provide a hazardous environment in which a preservative can be challenged by a range of micro-organisms. This paper presents the results of tests carried out to investigate the performance of wood preservatives in a wet ...
G R Williams, S Caswell
The performance of softwood species used as poles in Queensland
1985 - IRG/WP 1253
In Queensland, the conifer Pinus elliottii could provide material suitable for use as poles. Full size pole material has been readily treated with CCA with no significant loss in strength. Seasoning of logs prior to treatment requires particular attention in the wet tropical and sub-tropical regions of Queensland. Experimental and in service field tests have indicated excellent performance of CCA ...
L E Leightley
Use of the Pilodyn to assess deterioration of treated aspen waferboard after 30 months of outdoor exposure
1986 - IRG/WP 2254
Samples of preservative treated aspen waferboard exposed outdoors for 30 mo. were compared using pin penetrations of the 6 Joule Pilodyn. These results correlated well with rankings of treatment performance based on more laborious standard mechanical tests, and demonstrate the potential for use of the Pilodyn as a tool to evaluate wood composites in test exposures with minimal destruction....
E L Schmidt, M G Dietz
Acetylation of lignocellulosic materials
1989 - IRG/WP 3516
A simplified procedure for the acetylation of lignocellulosic materials has been developed. The acetylation is done with a limited amount of liquid acetic anhydride without the addition of a catalyst or an organic co-solvent. Dimensional stability and biological resistance are both much improved by the acetylation. Equilibrium moisture content in acetylated material is considerably lower than in u...
P Larsson, A-M Tillman
Treatment of wood with formaldehyde. Acid catalysis of the reaction between formaldehyde and wood
1980 - IRG/WP 3146
Formaldehyde reacts with the free OH-groups in wood forming cross-linking bonds. The reaction can be brought about without any catalyst but in that case the activation energy is very high and high temperatures and long reaction times are needed. Normally, the reaction is catalysed by different acids. Acid catalysts, however, tend to degrade the cellulose and the wood matrix causing reduction in th...
T Vihavainen, K Piispanen, P Mansikkamäki
Acetylated solid wood. Laboratory durability test (part 2) and field trials
1995 - IRG/WP 95-40048
Degradation of acetylated beech, pine and poplar by soft rot fungi was related to strength loss in a laboratory test. No strength loss was noticed for poplar acetylated to a weight percent gain (WPG) of more than 11.2% and beech with a WPG of 12.8%. Several field trials were set up to determine the durability of acetylated products in practice. They included a field test to determine the durabilit...
E P J Beckers, H Militz, M Stevens
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
Application of a novel strength evaluation technique during screening of wood preservatives
1986 - IRG/WP 2262
The effectiveness of CCA and ACA in treated aspen mini stakes tested using a novel bag procedure, with unsterile soil fortified with Chaetomium globosum and Ceratocystis albida, is reported. Good agreement between toxic limits determined using the standard weight loss procedure, and those determined by the strength technique were found, with some indication that the strength loss method is more se...
J N R Ruddick
Use of compression strength loss for measuring decay in the soil block test
1996 - IRG/WP 96-20083
The possibility of using radial direction compression strength of wood, rather than mass loss, was evaluated for both a brown-rot fungus (Gloeophyllum trabeum) and white-rot fungus (Trametes versicolor). With untreated pine wafers (5 x 19 x 19 mm³ - l x r x t) exposed to Gloeophyllum trabeum in a soil block test for five days, the compression strength loss was nearly 50% compared to a 5% mass los...
D D Nicholas, Zhongwei Jin
Three years of field tests with "Lignomer" stakes in ground contact
1981 - IRG/WP 3166
The "Lignomer" (Wood Polymer Composite) is a material obtained during the polymerisation of various monomers or its mixtures in wood. As laboratory tests have shown, this material is characterized by a high resistance against biological deteriorating agents. The laboratory investigations on the durability of various materials against biological deterioration are in many instances extended by field...
K Lutomski
Laser incising of spruce lumber for improved preservative penetration
1991 - IRG/WP 3646
Red spruce heartwood specimens were incised using a range of laser beam power levels and pulse durations. The penetration of CCA through these holes into the wood was monitored after pressure treatment. In addition, green and dried spruce samples were incised using two patterns with incision densities of either 16.1 holes/in² or 21.3 holes/in². Following CCA pressure treatment the samples were t...
B Goodell, F A Kamke, Jing Liu
Evaluation of a laboratory soft rot test on basis of weight loss and residual strength
1989 - IRG/WP 2336
Based on the principles of different previously reported experimental procedures dealing with laboratory soft rot testing, a study was conducted on treated poplar and beech. Preservatives used were CCA, CCF, AAC, Azaconazole and TCMTB. Treated samples were exposed for three months in a vermiculite substrate to Chaetomium globosum. Evaluation was based on absolute mass loss, percentage weight loss ...
W Verbeke, J Van Acker, M Stevens
Decay rates and strength and stiffness loss in foundation beams
1992 - IRG/WP 92-1563
The TNO Centre for Timber Research has executed an extensive research programme into the rate of decay in foundation beams, as a result of lowering of ground water tables. The aim of the research was to develop a method, predicting the decrease in strength and stiffness in beams, due to wood decay during drytime of foundation beams. With the calculated extremes in decay, the damage caused by local...
P Esser, H S Buitenkamp
Proposal for further work on accelerated ageing
1988 - IRG/WP 2314
M-L Edlund
Microbiological degradation of wooden piles in building foundations
1988 - IRG/WP 1370
White rot, soft rot and bacterial attack have been detected in softwood piles under buildings. In some cases bacteria were found to be the main degradation organisms in the studied piles. The water content of degraded piles was very high. The compression strength was quite low also in the piles deteriorated by bacteria. The density of wood was very variable, and the degree of degradation could not...
L Paajanen, H Viitanen
A comparison of soft rot, white rot and brown rot in CCA, CCP, CCF, CCB, TCMTB and benzalkonium chloride treated Pinus radiata IUFRO stakes, after 9-15 years exposure at five test sites in New Zealand
1991 - IRG/WP 1485
The aim of this study was to determine if decay type varies significantly between five field trial test sites of different soil type, aspect and climate in 9-15 year old, replicate CCA, CCF, CCP. CCB, TCMTB and AAC treated IUFRO stakes. A visual on-site assessment of decay type on every test stake was made and observations confirmed by microscopical examination. Regression analyses were used to de...
R N Wakeling
Finishes for outdoor timbers
1975 - IRG/WP 378
Anonymous
Field trial with poles of Scots pine treated with six different creosotes
1996 - IRG/WP 96-30115
In the middle of the 50's field trials with creosote-treated poles were started in France, Germany and Sweden. The trials were initiated by WEI (Western-European Institute for Wood Preservation). Six different creosotes were used and 40 poles per creosote were installed at each test field. Results after 39 years of exposure in Simlangsdalen, Sweden are reported. Poles treated with a heavy...
Ö Bergman
Wood preservatives: Field tests out of ground contact. Brief survey of principles and methodology
1976 - IRG/WP 269
This paper contains the following spots:
1.: The general need for field tests. 2.: Interests and limits of field tests in ground contact. 3.: Various methods in use for out-of-ground contact field tests. 4.: Fungal cellar tests are they an alternative to above-ground decay exposure tests? 5.: Conclusions....
M Fougerousse
Collaborative soft rot tests. Names and addresses of collaborators
1973 - IRG/WP 231
IRG Secretariat
Strength loss associated with steam conditioning and boron treatment of radiata pine framing
1987 - IRG/WP 3438
The combined effect of included defects and wood moisture content on the strength loss of second rotation radiata pine framing following conventional steam conditioning is investigated. The green Modulus of Elasticity (MOE) is reduced by approximately 13% after steaming. When dried after steaming, however, neither the MOE nor MOR is significantly different from unsteamed dried controls....
M J Collins, P Vinden
Co-operative studies on determining toxic values against wood-destroying Basidiomycetes: Progress report to May 1989
1989 - IRG/WP 2339
This document reports progress on the co-operative study between nine laboratories set up following the proposals contained in Document IRG/WP/2316. Results have been received from two laboratories. Toxic values data have been established successfully using the test fungus Coniophora puteana but problems have been encountered with the other test fungi....
A F Bravery, J K Carey
Moisture content levels and decay of hemlock
1986 - IRG/WP 1287
As a model of decay conditions of wooden members in wooden houses, a decay test was set up in which samples of western hemlock (Tsuga heterophylla) under 4 moisture levels were examined. Each week the samples were weighed and if the weights indicated that their moisture contents were lower than the expected levels, distilled water was added. Every 8 weeks 3 samples from each condition were oven dr...
K Suzuki
Marine testing of selected waterborne preservatives
1987 - IRG/WP 4137
In 1978 a marine test was established at West Vancouver, B C. to determine the performance of selected waterborne preservatives. The preservatives in test were chromated-copper-arsenate (CCA-C), ammoniacal copper arsenate (ACA), a modified formulation of ACA which contained a higher copper content (modified ACA), ammoniacal copper zinc arsenate (ACZA) and ammoniacal zinc arsenate (AZA). The wood s...
J N R Ruddick