Your search resulted in 425 documents. Displaying 25 entries per page.
Supply of wooden transmission and telephone poles in Tanzania: Problems and possible solutions
1987 - IRG/WP 3424
The eucalypts which have been used widely for utility poles for more than 30 years have dwindled remarkably from traditional supply areas. Consequently, pole-using authorities are considering importing poles from abroad. This alternative is considered unrealistic and costly. The aims of this paper are: - to dispel fears of pole scarcity and to show that an abundant resource of a variety of tree sp...
K K Murira, S A Diwani
A non-destructive testing technique for wood poles
1987 - IRG/WP 2293
A method has been developed to evaluate the stiffness and condition of a wood pole based on structural dynamics. This paper describes the results of tests performed on nearly 200 wood utility poles across Western Canada. A high correlation exists between the dynamic non-destructive test and direct mechanical tests. The need for an accurate non-destructive testing technique is demonstrated by the f...
W M Murphy, D E Franklin, R A Palylyk
Wood cement composites using spent CCA treated wood
1999 - IRG/WP 99-50126
The feasibility of using spent or out-of-service CCA treated wood as a component of wood/cement composites was evaluated. Cold pressed wood particle cement boards were made using CCA treated particles from a red pine (Pinus resinosa Ait.) pole removed from service and from untreated red pine wood from a new pole. Boards were manufactured using a range of wood to cement ratios and water to cement r...
Chen Huang, P A Cooper
Effect of soil chemistry and physical properties on wood preservative leaching
1998 - IRG/WP 98-50111
When treated wood is placed in contact with soil, complicated mass transfer and chemical reactions occur which causes the preservative components to leach from the wood. There are several factors that are known to affect the amount of chemical leached from wood. These are properties of the preservative and carrier, preservative retention, degree of fixation, exposure time, grain orientation, surfa...
Joan-Hao Wang, D D Nicholas, L S Sites, D E Pettry
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
A comparison analysis of eight strains of Serpula lacrymans (Schum. ex Fr.) S.F. Gray
1991 - IRG/WP 2362
Investigations were previously carried out to compare eight strains of Serpula lacrymans (Schum. ex Fr.) S.F. Gray (some used in various countries as standard test strains): FPRL 12C (England), FPRL 12E (Germany), Warsaw III (Poland), HFP 7802 (Japan), DFP 16508, 16509, 16521 and 16522 (Australia). Studies included growth rate and dry mass of mycelium, decay capacity, reduction of compression stre...
J Wazny, J D Thornton
Comparison of bluestain fungi growing in vitro and in vivo
1996 - IRG/WP 96-10149
Both moulds and bluestain fungi cause serious economic losses for forestry and timber processing industries and much research is aimed at finding environmentally and economically acceptable methods of control. It is especially important to study the growth of these fungi in freshly cut wood, which has been unaltered by drying or sterilisation, and which therefore resembles the substratum they woul...
A Uzunovic, J F Webber, D J Dickinson
Biological Control of Bluestain - Log Field Trials in Canada
2002 - IRG/WP 02-10423
In the summer of 2000 we ran two field experiments (in Alberta and British Columbia) to test the feasibility of using an albino bluestain isolate (Cartapip97TM) to protect lodgepole pine logs from being stained by wild-type bluestain fungi. Results showed that Cartapip applied at the recommended concentration significantly reduced the amount of stain found in the Alberta
trials. Cartapip applie...
A Uzunovic, D Minchin, A Byrne
Influence of the nutritional elements on pigmentation and production of biomass of bluestain fungus Aureobasidium pullulans
1997 - IRG/WP 97-10198
The effect of the carbon source and the amount of the nitrogen on the melanization and the production of mycelial mass of bluestain fungus Aureobasidium pullulans was studied by using solid state cultivations. The carbon sources used varied from easily soluble sugars to structural polysaccharides existing in lignocellulosic material. The amount of melanin was evaluated by using partial purificatio...
A-C Ritschkoff, M Rättö, F Thomassin
A questionnaire survey to establish the perceptions of UK specifiers concerning the key material attributes of timer for use in marine and fresh water engineering
2004 - IRG/WP 04-10519
Engineers have a key role in making informed decisions on the type of materials to be used in the schemes they design and construct. Currently, in England and Wales, it is believed that some £500m per year is invested in flood and coastal defence engineering. There is a lack of centralised data in the UK holding information on timber for usage in fluvial and, particularly coastal engineering. A...
J R Williams, G S Sawyer, S M Cragg, J Simm
Bamboo: A Material Rediscovered
2006 - IRG/WP 06-10577
Bamboo has resurfaced as a valuable raw material as an inexpensive substitute for wood and a variety of value added products for engineered composites. Being a fast growing material available in the tropics, its real value was not realized until recently. Property evaluation studies and efforts to develop processing methods were initiated in the bamboo growing countries in the nineteenth century....
S Kumar
Correlation between modulus of elasticity, mass losses and FTIR spectra of copper treated decayed wood
2006 - IRG/WP 06-10580
The composition of copper-based preservatives will change from copper-chromium to copper-ethanolamine, due to environmental demands. The most important drawback of copper-impregnated wood is the presence of tolerant fungal organisms that have developed an ability to degrade such preserved wood. In order to elucidate these processes, specimens (0.5×1.0×15 cm) made of Norway spruce (Picea abies) w...
M Humar, B Bucar, F Pohleven
Moldicidal properties of seven essential oils
2006 - IRG/WP 06-30404
When wood and wood products are exposed to moisture during storage, construction or while in-service, mold growth can occur in 24 to 48 hours. Mold growth could be suppressed or prevented if wood was treated with an effective mold inhibitor. The objective of this study was to evaluate the mold inhibiting properties of natural plant extracts such as essential oils. Seven essential oils were evaluat...
V W Yang, C A Clausen
Addition of boron compounds and octanoic acid for improvement of biocidal properties and copper fixation at copper-ethanolamine based wood preservatives
2006 - IRG/WP 06-30408
Copper-ethanolamine based wood preservatives became important active substance (formulation) for wood protection, novelty. As copper itself can not ensure sufficient protection against wood destroying organisms and fixation in wood we combine it with other biocides like ethanolamine, boron and octanoic acid. This investigates were performance on spruce wood impregnated with different combination o...
F Pohleven, M Humar
Heat treatment of less-valuable Nigerian-grown Ceiba pentandra wood for improved properties
2006 - IRG/WP 06-40332
The hardwood Ceiba pentandra locally known as “ araba “ in Nigeria is rarely used for structural and construction works due to its high dimensional instability, low strength and durability values. Samples (10 x 10 x 150mm) were removed from four green boards (25 x 200 x 3000mm) of this species originating from a natural forest stand in Nigeria and subjected to 2-hour heat treatment at 160°C a...
L Awoyemi
Copper borate for the protection of engineered wood products
2006 - IRG/WP 06-40334
Copper borate was evaluated for use in protecting oriented strand board (OSB) from mould, decay, and termites. Aspen OSB bonded with either phenolic or isocyanate resin was treated with several formulations of copper borate at various loadings from 0.26 to 4 percent by weight. These panels were then tested to determine the impact of the preservative on mechanical properties as well as resistance ...
R Smart, W Wall
Wood plastic composites from modified wood; Part 1 - Conceptual idea, mechanical and physical properties
2006 - IRG/WP 06-40338
Wood plastic composites, WPCs, are rapidly taking shares from preservative treated wood on the decking market. However, the long term performance of the WPC products in this application is uncertain. Therefore, in an attempt to increase the long term performance and durability, the substitution of the unmodified wood component with modified wood has been studied in the work presented in this paper...
P Larsson Brelid, B K Segerholm, M Westin, M E P Wålinder
The commercialisation of ThermoWood® products
2006 - IRG/WP 06-40339
The concept of thermally modifying timber is well established, which has achieved a limited market breakthrough to date. Commercial application has mainly occurred within Finland, though recent years has seen market gain in several other European countries. This paper reviews the known properties of ThermoWood® timber, based on the combined work of the Finnish ThermoWood® Association, alongside ...
D Jones, E Suttie, J Ala-Viikari, N Bergstrom, D Mayes
Effects of heat treatments on decay resistance and material properties of ponderosa pine and yellow poplar
2007 - IRG/WP 07-40374
The potential for using heat treatment to improve the properties of North American fenestration species was evaluated on ponderosa pine (Pinus ponderosa L) and yellow poplar (Liriodendron tulipifera L) treated using the ThermoWood process at various treatment temperatures and times. Soil block tests using Gloeophyllum trabeum, Postia placenta, or Trametes versicolor showed that durability was enh...
C Vidrine, C Freitag, J Nicholson, J J Morrell
Influence of ethanolamine on lignin depolymerization and copper leaching from treated Norway spruce and beech wood
2007 - IRG/WP 07-30423
Copper-ethanolamine based wood preservatives are replacing several classical copper-chromium based solutions, due to foreseen ban of chromium. Fixation of copper-ethanolamine based wood preservatives is not as good as fixation of copper-chromium ones. The main object of this manuscript was to prove, that ethanolamine is the prime reason for insufficient fixation of copper-ethanolamine formulations...
M Humar, B Bucar, M Zupancic, D Žlindra, F Pohleven
Mold resistance of heat-treated wood
2007 - IRG/WP 07-40358
The resistance of heat-treated sugi sapwood against three mold fungi was evaluated. Wood specimens were first subjected to heat treatments at 180 and 220ºC for 2 and 4 hours. Mold growth on the surface of the specimens was measured 1, 2, 4 and 6 weeks after the inoculation with the fungi in laboratory conditions. Laboratory decay tests were performed using two brown and white-rot fungi along with...
S N Kartal
Fire, flame resistance and thermal properties of oil thermally-treated wood
2007 - IRG/WP 07-40361
Oil thermal treatment, first developed by German scientists, is a promising technology for improving the durability and dimensional stability of wood for outdoor above-ground residential uses such as siding and shingles. The present authors’ previous research showed that 220ºC is an optimal treatment temperature, with 2 hours’ treatment producing wood with significantly improved moisture and ...
Jieying Wang, P Cooper
Effects of sodium hypochlorite on compression strength and copper retention of spruce wood treated with copper azole and alkaline copper quat
2007 - IRG/WP 07-40362
This work investigates the effects of sodium hypochlorite on compression strength values and copper retention ratios of refractory spruce wood (Picea oriental L.) treated with the waterborne preservative Copper Azole, (CBA-A, Tanalith-E 3492) and alkaline copper quat (ACQ-2200). Before the copper azole and alkaline copper quat treatment, the samples were immersed in 500 ml of sodium hypochlorite s...
S Yildiz, E Dizman, A Temiz, Ü C Yildiz
The effects of chemical modification on the biological properties of alder and spruce particleboards
2007 - IRG/WP 07-40363
This study is evaluated by measuring the weight loss, and the ability of white and brown-rot fungi to attack unmodified and modified particleboards manufactured using spruce (Picea orientalis (L.) Link.) and alder (Alnus glutinosa) chips. The chips were reacted with acetic, succinic, maleic and phthalic anhydride at constant temperature for 3 hours then, hot pressed at 150 °C by using phenol for...
Ü C Yildiz, E Dizman, S Yildiz, A Temiz, M Aslan, E D Gezer
Fire Safety of Wood Floor Assembly: Model and Full-scale Test
2007 - IRG/WP 07-20375
The present paper describes the model for the prediction of fire safety of wood floor assemblies. The model includes heat transfer model for the calculation of the flow of heat in floor assembly and structural model for the analysis of the mechanical performance of wood joists. The floor assemblies considered in this paper are constructed with nominal 2x10 (38x241mm) wood joists lined by Type X ...
H Takeda