Your search resulted in 183 documents. Displaying 25 entries per page.
Evaluation of a utility pole inspection procedure
1996 - IRG/WP 96-20084
Methods were developed and are currently being utilized to appraise residual strength of utility poles based on visual assessment of increment cores. Strength tests, mycological descriptions and anatomical analyses were performed on eight utility poles taken out of service and one new (never in service) pole. Samples were obtained from increment cores removed from 6 levels in the pole: 2 feet, gro...
S E Anagnost, C J K Wang
Supercritical fluid treatment: Effects on bending strength of white spruce heartwood
1993 - IRG/WP 93-20008
The effects of supercritical carbon dioxide on wood strength were evaluated using white spruce heartwood, a species known to be especially susceptible to collapse during exposure to higher pressures. The effects of pressures of 2000 or 3600 psig and temperatures of 40 or 80°C were evaluated using 30 or 60 minute exposure periods. No significant differences were noted in modulus of rupture or modu...
S M Smith, J J Morrell, E Sahle-Demessie, K L Levien
Fundamentals on steam fixation of chromated wood preservatives
1988 - IRG/WP 3483
Weathering of treated wood directly after impregnation leaches up to 2% of copper-chromate-containing wood preservatives. Almost total fixation of Cr+6 is achieved by steaming the treated wood at 100°C to 120°C, preferably 110°C. To initiate such spontaneous fixation 85°C to 90°C inside the wood are essential, which requires heating times ranging from 20 to 80 min, depending on timber species...
R-D Peek, H Willeitner
The comparative resistance to fungi of the wood munika (Pinus heldreichii Christ.), fir (Abies alba Mill.) and spruce (Picea excelsa Poir.) compared with Pinus sylvestris L. and some physical and mechanical characteristics of munika
1981 - IRG/WP 1129
The munika (Pinus heldreichii Christ.) is situated primarily in the Balkans, and partially in the south of the Apenine peninsula. As an endemic species, with a very little annual increment, it has not been used enough as a timber for mechanical conversion up till now, although the oldest trees can grow to 27 m in height, with a diameter at breast height of about 60 cm. According to data of many Ba...
M Petrovic, M Miric
Investigation of the suitability of silver fir (Abies alba Mill.) for thermal modification
2004 - IRG/WP 04-40275
In this study the suitability of silver fir (Abies alba Mill.) was examined for thermal modification. Comparative experimental investigations were performed with silver fir and Norway spruce (Picea abies Karst.) after thermal treatments. Besides properties, which characterize the quality of heat treatments, like dimensional stability and resistance against fungal attack, strength properties of the...
C Brischke, A O Rapp
The effect of rate of pressure application on preservative uptake along and across the grain of fir (Abies bornmulleriana Mattf.) at different ramp and constant pressure times
2004 - IRG/WP 04-20292
This study was particularly design to determine the preservative uptake at different ramp (rate of increase in pressure) and constant pressure times on longitudinal, tangential and radial penetrations of fir (Abies bornmulleriana Mattf.) which grown indigeneously in Turkey. The samples of 2 cm cubes of kiln-dried wood (nominated to 12% moisture content) were treated at different ramp times varied ...
I Usta
Standardization of preservative treated timber species for conductor, insulator and transformer packing of REB
1996 - IRG/WP 96-40071
In order to resolve the post landing failure problem of wooden packing for conductor, insulator, transformer of REB, the names of the suitable timber species from different parts of the world, irrespective of countries of origin have been standardized along with their strength and treatability grades. The CCA treatability of some Pakistani timber species have been presented for example which was t...
A K Lahiry
Preservative treatment of common timbers and bamboos of Bangladesh for rural electrification infrastructure
1998 - IRG/WP 98-40104
Researches revealed new treatment grades, treatment groups, grading groups, natural durability grades, strength groups and a new preservative combination for remedial treatment and sterilization of most common timbers and bamboos of Bangladesh. The obtained findings are applicable for equivalent timber species having equivalent climatic condition. Sapwoods are always perishable and timbers with wh...
A K Lahiry
Applicability of supercritical carbon dioxide to the preservative treatment of wood-based composites
2001 - IRG/WP 01-40199
Treatability of five structural-use wood-based composites (medium density fiberboard, hardwood plywood, softwood plywood, particleboard and oriented strand board) was evaluated when supercritical (SC) carbon dioxide (CO2) was used as a carrier solvent. Treatments were conducted at three temperature 32 levels (25, 35 and 45°C) and two pressure levels [80 kgf/cm2 (7,845 kPa) and 120 kgf/cm2 (11,768...
M Muin, A Adachi, K Tsunoda
Thermal modification of non-durable wood species 2. Improved wood properties of thermal treated wood
1998 - IRG/WP 98-40124
Properties of wood treated in a new heat-treatment process called the PLATO-process have been studied. Several wood species have been treated using this new thermal modification process using a range of process conditions (mainly time and temperature). In this study the characteristics of the treated wood were determined using samples from whole planks treated on pilot plant scale. The modified ch...
B F Tjeerdsma, M J Boonstra, H Militz
Bacterial degradation of Pinus radiata compression wood
1996 - IRG/WP 96-10153
An inspection of twelve year old, CCA-treated Pinus radiata wood from an industrial cooling tower showed extensive surface decay of wood. Electron microscopic examination of decaying compression wood indicated that compression wood cells were attacked exclusively by bacteria, which were of erosion and tunnelling types. As compared to the normal wood, compression wood appeared to be more resistance...
A P Singh, R N Wakeling
Improved preservative penetration of spruce after pre-treatment with selected fungi. II. Creosote treatment, analysis and strength testing
1998 - IRG/WP 98-40106
This paper describes the creosote treatment and analysis of logs pre-treated with selected fungal agents as a method of increasing the porosity of the wood prior to preservative treatment. The paper also reports the subsequent strength testing of the timber to evaluate the effects of the fungal pre-treatment on the structural integrity of the wood.
European spruce logs were pre-treated with eithe...
E J Tucker, A Bruce, H J Staines, B Rosner, K Messner
Alternatives to CCA-treated Pinus radiata as vineyard posts
2004 - IRG/WP 04-50212
An estimated 10 million trellis posts per year are used in Australian vineyards and about 75% of these are CCA-treated Pinus radiata. CCA-treated Pinus radiata posts are brittle and at times in short supply. Use of some products containing CCA is being restricted in Australia. Recently, plantation forestry has expanded rapidly for disposal of industrial and irrigation wastewater. Thinnings from th...
M Mollah, J Smith, K McCarthy, L J Cookson
Effects of air-seasoning on fungal colonization and wood strength of Douglas fir poles
1987 - IRG/WP 1315
Air seasoning economically reduces the moisture content of Douglas fir poles before pressure treatment with preservatives. Advanced decay in poles in service has resulted when decay fungi (Basidiomycetes) colonized poles during air-seasoning and survived the treatment process. These problems have led to recommendations to severely limit this practice. To determine the role of these fungi in peeled...
J J Morrell, M E Corden, R D Graham, B L Kropp, P Przybylowicz, S M Smith, C A Sexton
Methods for improving preservative penetration into wood: a review
2002 - IRG/WP 02-40227
Pressure treatment technologies have been available since the mid-1830's, but the processes used for wood treatment are still largely unable to overcome the fundamental limitations of flow through semi-permeable pit membranes. Instead, methods have arisen that attempt to improve treatability of the wood including incising, compression rolling, through boring, or radial drilling. Other a...
J J Morrell, P I Morris
Evaluation of bending strength by non-destructive methods of Ezomatzu with white pocket rot
1991 - IRG/WP 2371
The possibility of application of three non-destructive methods was examined for evaluation of bending strength of ezomatsu (Picea jezoensis CARR.) with white pocket rot. As non-destructive methods, the measurements of ultrasonic wave propagation time, impact-induced stress wave propagation time and penetration depth of pin of "PILODYN Wood Tester" were applied to compare with visual evaluation of...
T Tanaka
Preservation of wood composites with zinc borate
1995 - IRG/WP 95-30074
Inorganic borates such as boric acid, borax, disodium octaborate tetrahydrate, and zinc borate can be incorporated into wood composites such as waferboard to impart decay and insect resistance to the final product. Zinc borate is especially well suited for this application due to its efficacy and leach resistance. The paper summarizes the work performed to date in this area. The effects on strengt...
P E Laks, M J Manning
Effect of compression wood on leaching of chromium, copper, and arsenic from CCA-C treated red pine (Pinus resinosa Ait.)
2000 - IRG/WP 00-30232
In this study, the effect of compression wood formation on the release rate of chromium, copper, and arsenic elements from red pine (Pinus resinosa Ait) was investigated. Wood blocks from red pine containing compression and normal wood portions were treated with a 1.0% CCA-C solution and were then allowed to fix at 23 ± ??2°C (74 ± 4°F) for 0, 6, 24, 48, 96, 192, and 336 hours. After each fixa...
S N Kartal, S T Lebow
The influence of causing primary blue-stain fungus Ceratocystis imperfecta on selected properties of Scots pine wood
2002 - IRG/WP 02-10425
The effects of development in wood the fungi causing blue-stain on the wood properties are not univocal. There were been undertaken investigation to clear the influence of such fungi on selected physical and mechanical properties of Scots pine wood.
Wet sap wood samples of fresh cut Scots pine wood (Pinus sylvestris L.) were infested with pure culture of Ceratocystis imperfecta Mill. et Grenz and...
A Fojutowski
Mechanical properties of CCA-treated southern pine after post-treatment kiln drying
1989 - IRG/WP 3543
This report reviews current research dealing with the effects of waterborne preservative treatment and redrying on the mechanical properties of wood. In general, waterborne preservative treatments reduce average mechanical properties. This effect is exaggerated when treated wood is kiln-dried after treatment, especially at elevated temperatures. For lumber, recently completed research at the Missi...
H M Barnes, J E Winandy
Comparison of thermally modified wood originating from four industrial scale processes – durability
2002 - IRG/WP 02-40229
This study examined the differences in biological wood properties of heat treated wood originating from four different European industrial heat treatment plants. The manufacturers of heat treated material were: PLATO Hout B.V./Netherlands, Thermo Wood/Finland, New Option Wood/France and Menz Holz/Germany where Oil-Heat treated Wood (OHT) is produced.
The results of miniblock tests with basidiomyc...
C R Welzbacher, A O Rapp
Physical and mechanical properties of tea (Thea sinensis L.), kanak chura (Peltophorum pterocarpum (DC.) Baker ex Heyne ) and bottle brush (Callistemon citrinus Stapf. ) - Timbers grown is Bangladesh
1999 - IRG/WP 99-40141
The physical and mechanical properties, especially the strength, density, structure, colour, natural durability, workability, seasonableness and treatability of timbers of tea (Thea sinensis), kanak chura (Peltophorum pterocarpum) and bottle brush (Callistemon citrinus) grown in Bangladesh have been found out for the first time. The tea and bottle brush are completely treatable at dry condition an...
A K Lahiry
The effect of concrete embedment on CCA treated hardwood and softwood timbers
1985 - IRG/WP 3340
Small size stakes of Eucalyptus maculata and Pinus elliottii were treated with CCA to various retentions and embedded in concrete collars containing varying amounts of a fungicide additive. During the 30 month trial period stakes were removed after 12, 18, 24 and 30 months and assessed for residual strength. Stakes which showed significant strength reductions were microscopically examined for the ...
L E Leightley, G A Willoughby
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
Relationship between the bending strength and the degree of termite attacks on western hemlock by Coptotermes formosanus Shiraki
1990 - IRG/WP 1434
For the examination of the relationship between the bending strength and the degree of termite attacks, Western Hemlock (Tsuga heterophylla Sarg.) was used. Sixty specimens (4.5 x 4.5 x 82 cm³) were attacked by termites at the culture room of Coptotermes formosanus Shiraki. The termites were introduced on the central parts (10 cm) of specimens. In the case of the 2 points loading, the bending mom...
K Suzuki, T Tanaka