Your search resulted in 846 documents. Displaying 25 entries per page.
Natural decay resistance of some lesser-used tropical hardwoods from Ghana
2002 - IRG/WP 02-10438
Ghana is a tropical African country that is rich in diverse timber species. In order to reduce over-exploitation of the popular timber species and increase the resource base for the wood industry, lesser-used or lesser-known timber species are being promoted locally and for export. To do this successfully, it is essential to determine the physical, mechanical and biological properties of these tim...
S A Amartey, F R Hanson
Development of a turbidity method for the determination of water repellent in CCA treatment solutions
2000 - IRG/WP 00-40177
The use of aqueous water repellent emulsion formulations has increased significantly in the wood treatment industry. These are primarily used to enhance the weathering characteristics of wood products treated with water borne preservatives systems used in exterior above ground exposures. However, they are also used in pole treatments to improve the climbing characteristics and in low VOC millwork ...
P J Walcheski, L Jin
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
Influence of pre-swelling conditioning on swellometer results for CCA and water repellent additive treated wood
1997 - IRG/WP 97-20125
The pre-test moisture content and conditioning history of wafers cut from wood treated with CCA and an emulsion water repellent additive can dramatically influence swelling curves generated using a standard swellometer apparatus. The rate of water uptake and swelling increased significantly as wafers were dried to lower moisture contents prior to immersion swelling. The pre-swelling conditioning h...
A R Zahora
Investigation on different variation factors in the results of mycological test and means to reduce and avoid them
1986 - IRG/WP 2264
In order to clarify the causes of the dispersion observed in the results obtained with mycological tests made in accordance with standard EN-113, different factors assumed to be sources of the variations were studied. These included the moisture content of the test samples during the test, the influence of certain technological properties of the wood, the virulence of the fungus strains, the metho...
D Dirol
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
Evaluation of the corrosivity of the treated wood - Laboratory vs field test methodologies
2000 - IRG/WP 00-20211
The corrosivity of treated wood to fasteners has been evaluated using laboratory test procedures, including AWPA Standard E12-94. The standard method was modified in order to allow detailed study of commercial metal fasteners in terms of sample types, installation configuration and exposure conditions. Parallel field tests were also performed. The experimental results generated from these tests su...
L Jin, A F Preston
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
Evaluating the natural durability of native and tropical wood species against Reticulitermes flavip
2004 - IRG/WP 04-10539
Environmental pressures to eliminate arsenate from wood preservatives has resulted in voluntary removal of CCA for residential applications in the United States. A new generation of copper organic preservatives has been formulated to replace CCA for decking and in-ground applications but there is no guarantee that these preservatives represent a permanent solution to all related problems. There...
R A Arango, F Green III, K Hintz, R B Miller
Evaluating possibilities of leaching of deltamethrin and TCMTB (insecticides and fungicide for protecting wood) by rain water or by soaking in water
1988 - IRG/WP 3464
Deltamethrin and TCMTB have been subjected to several field leaching tests on freshly fallen trees and in the laboratory, using standard EN 84. All the trials gave the same results and confirm that Deltamethrin and TCMTB are not washed out after they have been allowed to penetrate the trunk surface properly. According to the EN 84 standard, less than 1% Deltamethrin and less than 1.7% TCMTB were r...
J S Duguet, V Dartigues
Treatment of lumber with preservative/water repellent emulsions - The significance of shear stability on penetration
1997 - IRG/WP 97-20124
Currently, the treatment of lumber with a water repellent emulsion and a wood preservative formulation in combination is the most cost effective way to prevent decay and to maintain the appearance of uncoated lumber in service. Water repellents influence the movement of moisture into and out of wood and, by so doing, can decrease checking and splitting significantly. Adequate penetration of the em...
F Cui, K J Archer
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
Fungal-termite associations in the natural resistance of selected eucalypt timbers
1978 - IRG/WP 173
Butt billets of Eucalyptus regnans F. Muell., Eucalyptus grandis W. Hill ex Maiden, and Eucalyptus camaldulensis Dehnh., showing no visible signs of decay, were examined for the presence of fungi in outer, middle and inner heartwood. Fungi obtained in pure culture were characterized. Eucalyptus regnans yielded Cytospora eucalypticola van der Westhuizen, Trichoderma harzianum Rifai and Penicillium ...
D B A Ruyooka
Contradiction between uptake of preservative in practical situation and laboratory testing
1992 - IRG/WP 92-2392
By brush treatment water- and solvent-based products were applied on boards of Scots pine and Norway spruce to achieve an uptake of 100 and 200 g/ml. In addition the scope of work to achieve the required uptake of preservative was determined under practical conditions for both product groups. EN 113 (RAL-GZ 830) tests were carried out to test the biological efficacy of products. After 18 months ex...
R Gründlinger, O Janotta, M Melzer
Fungicidal activity of some new water borne copper octanoate based formulations
1999 - IRG/WP 99-30198
Four new water borne formulations for preservation of wood were prepared: the composition of Cu(II) octanoate, 2-aminoethanol (ethanolamine) and water; the composition of complex of Cu(II) octanoate with nicotinamide, 2-aminoethanol and water; the one of Cu(II) octanoate, organic boron complex, 2-aminoethanol, dimethyl sulfoxide and water and finally, the mixture of Cu(II) octanoate, diazene, 2-am...
M Petric, M Pavlic, F Pohleven, P Segedin, B Kozlevcar, S Polanc, B Stefane, R Lenarsic
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
Marine exposure assessment of the natural resistance of a number of lesser known species of tropical hardwoods to teredinid and limnoriid borers
2004 - IRG/WP 04-10520
Naturally durable species of timber are used as an alternative to preservative treated timber for marine structures, but many species have not been evaluated for their potential for use in this environment. EN 275 specifies a 5-year test period - too long a period for screening tests to be economically viable. In this study, candidate timber species were selected for testing in the sea on the basi...
J R Williams, S M Cragg, L M S Borges, J D Icely
The degradation of wood surfaces by water
1984 - IRG/WP 3289
Thin radial/longitudinal sections (~100 µ) of Scots Pine (Pinus sylvestris) and lime (Tilia vulgaris), were exposed to deionised water over the temperature range 25-65°C. Losses in wet tensile strength and toughness occurred rapidly at temperatures from about 50°C upwards. After about 2 months' exposure pine lost some 10-30% of its tensile strength and 20-60% of its toughness. For lime...
W B Banks, P D Evans
Application of roller-pressing method to the novel liquid impregnation treatment of green timber
2001 - IRG/WP 01-40198
A transverse compression technique enabled us to impregnate liquid into green timber through replacement of the free water in the timber with a treatment liquid without any critical physical damage to the timber by the roller-pressing method. The roller-pressing is supposed to remove free water the cell cavities and to concurrently introduce the treatment solution into green timber in the treatmen...
M Inoue, K Adachi, K Tsunoda, Y Imamura, S Kawai
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
Evaluating the performance of preservative/water repellent emulsion systems
1997 - IRG/WP 97-20127
Water repellent emulsions are being combined with wood preservatives to improve the weathering properties of treated wood in service. Unfortunately, few standard procedures are available to objectively compare the performance of these systems and as a result quality issues are almost completely neglected. The value of swellometer tests, water immersion tests and accelerated weathering regimes in t...
K J Archer, F Cui
Soft rot - Soil burial - Tests. Influence of the water content of the soil on wood decay
1972 - IRG/WP 212
The decay of wood samples buried in the soil is influenced by various factors. Decisive are the water content, the content of organic substances, pH-value content of mineral nutritive substances etc. of the soil. For the tests, carried out by the EMPA until now, it was always started with a water content of 35%, refered to the dry weight of the EMPA-soil = 75% of its water capacity. In order to in...
O Wälchli