Your search resulted in 286 documents. Displaying 25 entries per page.
Leaching of copper-chrome-arsenic treated timber: Simulated rainfall testing
1996 - IRG/WP 96-50074
Six kiln dried radiata pine sapwood packs of timber were preservative treated with copper-chrome-arsenic preservative using a modified Bethell treatment schedule. The packs were then subjected to simulated rain leaching at specified periods after treatment. Higher chromium leachate was obtained when higher volumes of simulated rainfall were applied. Lower chromium leachate was obtained for timber ...
S Walley, P R S Cobham, P Vinden
A quantitative weathering study of wood surfaces modified by chromium VI and iron III compounds
1989 - IRG/WP 2330
Thin veneers of Pinus radiata were treated with dilute aqueous solutions of chromium VI and iron III compounds and exposed to natural weathering for 35 days. Zero-span tensile strength and weight losses of treated veneers were compared with losses observed in untreated specimens In a study designed to demonstrate the applicability of strength and weight loss measurements to the rapid quantitative ...
P D Evans, K J Schmalzl
The relationship between preservative type and surface degrade in Pinus radiata
1980 - IRG/WP 3158
Samples of Pinus radiata D. Don were impregnated with one of two preservative types, a copper chrome arsenic salt and a light organic solvent preservative. The panels were exposed to the weather for 4-5 years at a site near Sydney, Australia. Macroscopic and microscopic examinations showed different rates and patterns of weathering between the samples treated with each preservative and an untreate...
R S Johnstone, R K Bamber
Surface characteristics of wood treated with various AAC, ACQ and CCA formulations after weathering
1991 - IRG/WP 2369
Wood samples treated with various alkylammonium compounds (AACs) as well as ammoniacal copper quat (ACQ) and chromated copper arsenate (CCA) have been studied in accelerated weathering experiments. Microscopic examination of the surfaces of these samples after exposure in a weatherometer revealed several different changes. Samples treated with didecyldimethyl ammonium chloride (DDAC) show consider...
L Jin, K J Archer, A F Preston
Blue stain in timber in service. Preliminary results of the IRG collaborative tests to compare natural and artificial weathering
1978 - IRG/WP 286
The collaborative programme was initiated at IRG Meetings in Wildhaus, 1976. The six collaborators were BAM (Berlin), Cuprinol Ltd (UK), EMPA (Switzerland), GORI (Denmark), PRL (UK) and Imperial College (UK). Experimental plans were finalised in December 1976 and panels treated by Cuprinol Ltd early in 1977. Natural weathering was carried out by BAM, Cuprinol, EMPA, GORI and PRL during April-Septe...
A F Bravery, D J Dickinson
Tropical In-Ground Durability of Structural Sarawak Hardwoods Impregnated to High Retention with CCA-salts, CCA-oxide and FCAP after 20 Years Exposure
2005 - IRG/WP 05-30384
Statistical analysis (ANOVA) was conducted on durability (termite and decay combined) rating data collected over 20 years exposure period of over 140 species of Sarawak timbers with altogether 30,000 stake specimens, at the Forest Department’s Sibu “graveyard” stake test sites from 1977. About 20 replicated stakes were pressure-treated to refusal with 10% g/ml concentration of up to 3 CCA-sa...
Wang Choon Ling, A H H Wong
Surface checking of CCA-treated radiata pine decking timber exposed to natural weathering
2000 - IRG/WP 00-40165
A field trial was established at four locations in Australia to assess the effect of CCA and CCA-wax treatment on the checking (cracking) of radiata pine decking timber exposed to natural weathering. Untreated decking timber and timber that had been pressure treated with water acted as controls. After 1 year's exposure the number and sizes of checks occurring in treated timber and control...
P D Evans, P J Beutel, C F Donnelly, R B Cunningham
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
Study on leaching of a magnesium fluorosilicate product (SF salt) from wood-boards by rain in the open and by artificial shower
1976 - IRG/WP 264
The test was performed in 1961 to obtain information about (1) the comparative leaching effect of natural rain and of artificial shower in the laboratory; (2) the comparative leaching effect on the active ingredient in proportion to the dye-stuff of the product. The results show that a continuos light rainfall with low precipitation has a much stronger leaching effect than short heavy showers with...
S Cymorek
Microscopic FT-IR depth profiling study of photo-induced degradation in wood
2001 - IRG/WP 01-20229
FT-IR microspectroscopy was used to monitor the changes in the chemical composition at various depths from the photo-irradiated surface of sugi (Cryptomeria japonica D. Don) sapwood. The radially cut wood face was exposed to artificial solar radiation from a xenon light source at 375 Wm-2 (in a 300 - 700 nm spectral range) for up to 600 h. The IR depth profiling spectra showed that the artificial ...
Y Kataoka, M Kiguchi.
Surface protection of wood with titanium, zirconium and manganese compounds
2005 - IRG/WP 05-30376
Thin radiata pine veneers were treated with a range of titanium, zirconium and manganese compounds and exposed to natural weathering. Veneer weight and tensile strength losses were used to assess the protective efficacy of the compounds. The oxidative manganese compounds potassium permanganate and manganic acetate restricted both weight and tensile strength loss of treated wood veneers during weat...
K J Schmalzl, P D Evans
Testing blue stain fungicides for joinery timber in combination with natural weathering
1976 - IRG/WP 268
Joinery timber in outside use becomes affected by blue-stain after a short time of exposure. This is especially the case with pine sapwood treated with unpigmented lacquer, but also with other timber species as well as different types of surface treatment. According to the basic investigations of BUTIN this is due to special types of blue-stain fungi, called "Lack-bläue" (lacquer blue-stain), in ...
H Willeitner
FTIR studies on the weathering of didecyldimethylammonium compound (DDAC) treated wood
1993 - IRG/WP 93-30013
Wood treated with alkylammonium compounds (AACs), such as DDAC, weathered more rapidly than untreated wood. In order to examine the influence of DDAC treatment of wood on its weathering, treated and untreated microtomed sections of southern yellow pine earlywood of various thicknesses, were prepared and weathered for approximately one month. The changes in these samples were monitored using FTIR. ...
R Liu, J N R Ruddick
A comparison of analytical and visual techniques used for assessment of weathering properties of chromium and copper azole treated timber
1994 - IRG/WP 94-20023
The weathering properties of preservative treated timber were studied by measuring surface lignin loss and by microscopic examination after weathering, and results were related to qualitative assessments of visual appearance after weathering. Measurement of relative rates of delignification of untreated and preservative treated timber obtained by FTIR analysis, and weight loss determined on thin v...
J A Cornfield, M D C Hale, G Fettis
Comparative study of blue stain resistance of various types of wood stains after artificial and natural weathering
1992 - IRG/WP 92-2411
For the determination of the protective effectiveness of a preservative treatment against blue stain in service, artificial weathering has been proposed as an alternative for the natural weathering period of 6 months in the European standard EN 152. Research on a range of products and on complete finishing systems for external joinery was conducted during 1986-1990. It revealed that the decisions ...
J Van Acker, M Stevens, M Nys
Preliminary observations of the effect of growth ring orientation on the surface checking of flat sawn Southern pine decking
2005 - IRG/WP 05-20313
Checking in decking timber is a serious defect and methods of reducing its severity are required to ensure that wood can compete with alternative decking materials. The first aim of this research was to test the hypothesis that flat sawn Southern pine decking boards with growth rings oriented concave to the exposed surface will develop less severe checking when exposed outdoors than similarly expo...
K Urban, P D Evans
Impregnation of timber with tannin as a mean of improving its dimensional stability
1992 - IRG/WP 92-3695
The results of a joint project carried out at the Timber Division of LNEC under the 2nd research programme of the CEC DGXII - "Wood as a renewable raw material" entitled "Stabilization of wood by impregnation processes" is presented. Pieces Maritime pine timber was impregnated with tannin under pressure to see if the treatment with tannin improved the behavior of wood regarding its dimensional sta...
J S Machado
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
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
Laboratory Evaluation of Soft Rot Resistance of Non-Durable Lesser-Known Malaysian Hardwoods
2006 - IRG/WP 06-10582
Resistance of six non-durable lesser-known Malaysian hardwoods, Pulai (Alstonia spp.), Rubberwood (Hevea brasiliensis), Ludai (Sapium spp.), Jelutong (Dyera costulata), Gaham Badak (Blumeodendron tokbrai) and Kayu arang (Diospyros spp.) compared with temperate Scots pine sapwood (Pinus sylvestris), were evaluated using the unsterile soil burial (mixed with Chaetomium globosum) versus vermiculite-b...
A H H Wong
Enhancing the Performance of Transparent Coatings by UV Protective Pre-treatments
2006 - IRG/WP 06-30399
Most industry observers anticipate a change from copper-based preservatives to metal-free combinations of organics for residential treated wood products in North America within the next one to five years. While the chromium copper provide considerable protection against UV, metal-free formulations will need UV protection in the form of additives or coatings. While transparent coatings can be made ...
P I Morris, S McFarling
L-joint based testing for service life prediction of exterior plywood in out of ground contact conditions
2006 - IRG/WP 06-20342
Good biological performance of several plywood types in exterior conditions is most probably related to altered wood moisture behaviour compared to solid wood. Therefore a test set up was developed, using EN 330 L-joint testing methodology, to facilitate differentiation of plywood for exterior applications.
The proposed test set up is an adaptation of an accelerated L-joint method introduced by V...
J De Smet, I De Windt, J Van Acker
High-energy multiple impact (HEMI)-test – Part 1: A new tool for quality control of thermally modified timber
2006 - IRG/WP 06-20346
Thermal modification processes improve durability and dimensional stability of wood, but the strength properties, especially the dynamic ones, are compromised and need to be considered with respect to industrial quality control. Results from standard dynamic strength testing, such as impact bending tests, suffer from high variability, and therefore require a high number of replicates. To overcome ...
C Brischke, A O Rapp, C R Welzbacher
Wood-Plastic Composites and the Durability Dilemma: Observations from the Field
2006 - IRG/WP 06-40351
Wood-Plastic Composites (WPCs) used for decking, window & door moldings have experienced dramatic growth in North America over the last several years, with annual production increasing at rates greater than 20% 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 t...
M J Manning, F M Ascherl, M E Mankowski
Laboratory Leaching Tests to Study the Effects of Post-Treatment Storage Periods on CCA Leachability and Fixation in Treated Permeable and Refractory Malaysian Hardwoods
2006 - IRG/WP 06-50240
The biological resistance and environmental safety of CCA-treated wood relies on the extent of post-treatment storage fixation of CCA in wood prior to being utilized. A study on the comparative leachability (fixation) of CCA-treated refractory and permeable heartwoods of 3 Malaysian hardwoods subjected to different post-treatment storage (fixation) periods of up to 4 weeks, at 2 laboratory leachin...
A H H Wong, H C Lai, N P T Lim