Your search resulted in 391 documents. Displaying 25 entries per page.
Moisture distribution in coated wooden panels. Studies of moisture dynamics by computerized axial tomography
1992 - IRG/WP 92-2413
Certain modern coatings have been held responsible for the rot damages in wood sidings, which have, during the past few years, appeared at an increasing extent in Scandinavia and which have occurred rather soon after the application of the coating. In this study, the moisture excluding effect of different coating systems intended for sidings have been studied with the help of an X-ray technique, c...
J Ekstedt, L O Lindgren, S Grundberg
Co-operative research project on L-joint testing. Sampling after 4 years exposure
1987 - IRG/WP 2274
In September 1983, Document No: IRG/WP/2208 was distributed giving guidance on sampling after 8 months exposure and including tables on which to record the test results. Similarly in September 1984, Document No: IRG/WP/2233 was distributed concerning sampling after 18 months exposure. No major problems have been notified to Princes Risborough Laboratory concerning the sampling method. It is theref...
J K Carey, A F Bravery
Treatment groups and remedies for CCA treated hardwood and softwood poles
1999 - IRG/WP 99-40142
Different hardwood and softwood species from Bangladesh and Bhutan was investigated regarding density, green fiber stress, natural durability of heartwood and CCA treated sapwood, CCA treatability grades, sapwood thickness, and kiln-drying properties for long term use as electric poles. These properties along with the past service records for nineteen years, separated ten heardwood and five softwo...
A K Lahiry
Thickened boron treatment
1990 - IRG/WP 3632
Commercial trials with thickened boron preservatives "Diffusol™" indicate a number of advantages when compared to traditional methods of dip-boron preservative treatment. These include: (i) more even uptake and distribution of preservative on and within the timber; (ii) faster diffusion times; (iii) the treatment of gauged timber (though improved retention); (iv) saving in energy costs (heating ...
P Vinden, J A Drysdale, M Spence
The development of a new boron-based wood preservative
1995 - IRG/WP 95-30085
The paper describes a new boron based wood preservative for the treatment of green timber. The product offers many benefits over conventional boron diffusion treatment including: 1. high viscosity, high concentration formulation; 2. permits dip treatment of a wide range of sawn board and pole sizes at ambient temperatures; 3. permits full cross section diffusion of borates without block stacking a...
P Turner, D Conradie
The movement of iron into field test stakes
1987 - IRG/WP 2284
Failed and sacrificial stakes recovered from the Westham Island field test site were examined for their iron content. Varying amounts were recorded, which were greatest in the failed stakes. The possible role of the iron taken up by the below ground portion of the stakes, in accelerating the decay process and/or the preservative leaching is under investigation. The reaction of the iron with the ch...
J N R Ruddick, P I Morris
A technique for determining the efficacy of water diffusible preservative plugs for implanting in joinery in service
1987 - IRG/WP 2291
A technique is described for determining the efficacy of soluble, diffusible preservative plugs for eradicating decay in joinery. It uses blocks of Scots pine sapwood or heartwood adjusted to known moisture contents prior to the establishment of the test fungus Coniophora puteana, from a single longitudinal dowel and the subsequent introduction of the preservative plugs. Prevention of decay, eradi...
J K Carey, A F Bravery
Application of oscillating pressure to improve treatability of refractory species
1987 - IRG/WP 3449
Under practical conditions a minimum moisture content of 80% demande by the German quality standard RAL-RG 411 can not be guaranteed throughout the year. Storage of logs with bark prolonges the drying process; a storage without bark must be avoided. A sufficient penetration according the standard can be achieved at least with a moisture content of 60%, optimal conditions may prevail between 100% a...
R-D Peek
The effect of moisture content on the electrical resistance of timber as detected by a pulsed current reistance meter (Shigometer)
1984 - IRG/WP 2212
The literature concerning the use of the Shigometer® for detecting decay in standing trees and wood poles is reviewed and the differences of opinion over the effect of timber moisture content on electrical resistance are highlighted. A simple experiment designed to test this effect is described and the implications of the results for testing poles in service are discussed. There was a large diffe...
P I Morris, D J Dickinson
The study of blue stain found in coniferous timber in SR Slovenia (Yugoslavia)
1983 - IRG/WP 1177
The report concerns the problems connected with blue stain in coniferous timbers stored in warehouses at wood-processing plants in SR Slovenia (Yugoslavia). The amounts of spruce-wood (Picea abies Karst.) found to have been infected with blue stain have been measured and some of the fungi causing the stain have been identified and their biology studied. It was found that the percentage of spruce-w...
R Benko
Anti-sapstain chemicals for diffusion treatment of rubber wood
1986 - IRG/WP 3367
Performance of Sinesto B and Akzo EN 494, two formulated products of alkyl ammonium compounds, was tested as fungicidal additive in the boron solution to control mould and stain during diffusion storage of rubber wood. Sinesto B at 2.0% (a.i.) concentration has given good control over mould and its protection against sapstain was only satisfactory. Akzo EN 494 at 0.7% (a.i.) concentration has give...
R Gnanaharan
Moisture content of logs under sprinklers
2000 - IRG/WP 00-40157
Logs are kept under sprinklers during storage for avoiding the development of sapstain fungi. According to literature, sapstain fungi do not develop if the moisture content is above 120%. It is supposed that, the water sprinklers maintain the log's moisture content above this value, but, very often, sapstain is found on sawn lumber cut from these logs. Logs are harvested and transported t...
M C Rose, A M Briones, M Fernández
Moisture content and other tested values in. Double layer tests of different size in Lithuania and Germany
2004 - IRG/WP 04-20299
The paper presents measurement results of moisture content and the analysis of durability trial of double layer wood in variants of varying size, conducted in Girionys, Kaunas distr., Lithuania and in Hamburg, Germany. In this trial 3 sample sets of varying size, containing 25, 50 and 100 specimens, are used. The aim of this trial is to ascertain an optimal number of test specimens. The dynamics o...
J Saladis, A O Rapp
Whitewood - An external joinery timber?
1975 - IRG/WP 253
The timber used traditionally for softwood joinery in the UK is redwood (Pinus sylvestris). In the past its ready availability in the desired sizes and quality and its durability in service encouraged little competition. However, the past decade has seen some erosion of this position, particularly through the increased proportion of sapwood in redwood supplies. Since the sapwood is less durable th...
J W W Morgan
The use of lap-joints in natural durability testing: moisture content development during 36 months outside exposure trials
2000 - IRG/WP 00-20217
Lap-joint trials (following European Standard ENV 12037) were set up with 11 different softwood and hardwood species. The main aim was to evaluate the suitability of this test standard (developed for testing wood preservative effectiveness) for natural durability testing. The moisture development has been followed during a 36 months period. In this paper, the outcomes of different moisture content...
H Militz, C J Bloom
Moisture Adsorption Behaviour of Rubber Wood Decayed by Brown and White rot Fungi
2005 - IRG/WP 05-40306
Moisture adsorption behaviour of rubber wood blocks decayed by each brown rot and white rot fungi was studied. The adsorption isotherms of decayed wood were compared with the isotherm of undecayed wood. The wood decayed by brown rot adsorbed less moisture as compared to sound or undecayed wood at all humidity levels. No significant difference was observed in adsorption behaviour of white rot dec...
S S Chauhan, H C Nagaveni
Water transfer in wood in relation to fungal attack in building - Effect of condensation and diffusion
1992 - IRG/WP 92-1543
Wood is continuously exchanging moisture with the surrounding atmosphere, the temperature and relative humidity are important factors. Wood moisture in this case is not enough to provoque decay by fungi. However, when, during the night, condensation appears cyclically, wood absorbs water and moisture content may be sufficiently high to allow development if drying does not take place. The water tra...
D Dirol, J-M Vergnaud
Why don't more people work with Serpula lacrymans nowadays? A discussion of some of the different approaches to experimenting with this unique fungus
1989 - IRG/WP 1383
Remarkably few laboratories are currently investigating this well-known fungus. Not only has it failed to gain acceptance as a standard test organism (for wood preservative evaluation) in many countries, but is also sometimes excluded from pure research studies when it ought to be an obvious first choice as a representative basidiomycete. This paper discusses some different approaches that have be...
J D Thornton
Borate diffusion from fused borate rods in douglas-fir transmission poles
1994 - IRG/WP 94-30042
Pressure-treated utility poles have given many years of excellent service, but their lifetime is often shortened by internal decay of the untreated heartwood center, particularly in refractory species, such as Douglas-fir. This paper reports the distribution of boron from fused borate rods installed in CCA-treated Douglas-fir transmission poles. The boric acid equivalent was roughly monitored by t...
T L Highley, W Finney, F Green III
Suitability of different termite species for laboratory testing
1982 - IRG/WP 1159
Different termite species were tested in the laboratory to evaluate the effectiveness of insecticides and wood preservatives in wood against termite attack. Determined were the optimum group size and composition, the matrix (vermiculite) volume and its moisture content. Choice feeding tests with fully impregnated wood blocks which are carried out according to a modified EN 117 procedure for Reticu...
U Kny, H Kühne
Redistribution of boric acid in radiata pine during drying after preservative treatment
1993 - IRG/WP 93-40010
Samples of 100 x 50 mm² radiata pine were processed with a variety of options to produce dry, boron-treated wood. Concentrations of boric acid in the central one-ninth and in the whole of the wood cross-sections were determined by chemical analysis and compared. Diffusion treated material was dried by air, conventional kiln (70/60°C), or high temperature kiln (120/70°C). Four different predryin...
A J Bergervoet, D R Page, J A Drysdale
A new process for in situ polymerization of vinyl monomers in wood to delay boron leaching
1998 - IRG/WP 98-40110
Efforts were accelerated on effective use of boron compounds in wood preservation owing to their environmentally safe characteristics and relatively low costs in addition to their well-known high bioactivity and fire resistant properties. Although having these unique favorable properties, they are readily leachable from treated wood at humid conditions. Therefore, they had limited market for exter...
M K Yalinkilic, W Dwianto, Y Imamura, M Takahashi
Penetration of oil-borne preservatives in American elm
1975 - IRG/WP 355
Pressure treatment of elm posts and cants by Rueping schedules resulted in erratic penetration. Instead of the expected gradual decrease in retention from surface inward in posts, inner zones frequently contained more preservative than the surface quarter inch. Heartwood was found penetrated when sapwood was not. There were numerous skips in treated zones. The prevalence and possible causes were i...
E A Behr
Protection of pine sawtimber and sawn timber against blue stain in Poland
1983 - IRG/WP 3193
The purpose of this paper is the synthesis of more important results of basic and applied research that have been grouped in the following problems: 1.: Fungi causing blue stain in the pine wood, occurring in Poland. 2.: Moisture content changes of pine sawtimber and sawn timber as the factor of blue stain producing fungi development. 3.: Effect of sapwood moisture content on the degree of wood st...
E Tarocinski, M H Zielinski
Factors affecting the resistance of fibre building boards to fungal attack
1975 - IRG/WP 252
Fungal decay is initiated at lower moisture contents in standard and tempered hardboards (18%) than in pine sapwood (26%). In contrast, in a saturated atmosphere, the equilibrium moisture contents of standard hardboard (14%) and of tempered hardboard (12.5%) are much lower than the moisture content permitting decay initiation whilst the equilibrium moisture content of pine sapwood (25.1%) approach...
C Grant, J G Savory