Your search resulted in 206 documents. Displaying 25 entries per page.
Nondestructive assessment of biodegradation in southern pine sapwood exposed to attack by natural populations of decay fungi and subterranean termites
1994 - IRG/WP 94-20042
Field methods for evaluating decay resistance of experimentally treated materials lack a means for quantitative measurement of residual strength. Quantitative relationships between speed of impact-induced waves travelling parallel to the grain and residual compressive strength have been demonstrated in softwood attacked by brown rot-decay fungi, but the effects of termites have not been documented...
R C De Groot, R J Ross, W Nelson
Studies and experiences of occurrence and development of soft rot in salt-treated poles of pine (Pinus sylvestris) installed in Swedish transmission lines in the years 1940-1945
1977 - IRG/WP 277
The present work describes the result of microscopic examinations of some 2,000 borings extracted from 20 to 23-year-old salt-treated poles (Scots pine) from the southern and central parts of Sweden. The purpose was to map out the occurrence of soft rot in Sweden and its influence on the mechanical strength of the poles as well as to contribute to the development of new and more satisfactory metho...
H Friis-Hansen
Biodetioration and strength reductions in preservative treated aspen waferboard
1983 - IRG/WP 2195
Experimental aspen waferboards, bonded with liquid or powdered phenol formaldehyde resins and treated by various methods with a wide selection of preservatives, were tested for fungal resistance in accelerated laboratory trials. Mold growth on the surface as well as weight and strength losses due to the actions of decay fungi were determined. Testing of board strength after decay in high and moder...
E L Schmidt, H J Hall, R O Gertjejansen, R C De Groot
Biological durabilityof cement-bonded particleboard
1997 - IRG/WP 97-20115
Cement-bonded particleboard (CBP) is a panel product manufactured from a combination of wood particle and cement with various ratio. The wood particle is used as reinforced material and the cement as an inorganic binder. Because of its many excellent properties, such as high weathering resistance, sound attenuation, and good acceptance for a range of surface treatments, CBP is widely used as a fac...
Qiao Wang, M Takahashi
Three years of field tests with "Lignomer" stakes in ground contact
1981 - IRG/WP 3166
The "Lignomer" (Wood Polymer Composite) is a material obtained during the polymerisation of various monomers or its mixtures in wood. As laboratory tests have shown, this material is characterized by a high resistance against biological deteriorating agents. The laboratory investigations on the durability of various materials against biological deterioration are in many instances extended by field...
K Lutomski
Laser incising of spruce lumber for improved preservative penetration
1991 - IRG/WP 3646
Red spruce heartwood specimens were incised using a range of laser beam power levels and pulse durations. The penetration of CCA through these holes into the wood was monitored after pressure treatment. In addition, green and dried spruce samples were incised using two patterns with incision densities of either 16.1 holes/in² or 21.3 holes/in². Following CCA pressure treatment the samples were t...
B Goodell, F A Kamke, Jing Liu
Major insects attacking timber used for building purposes and a practical approach for their control
1990 - IRG/WP 1449
Lignocellulosic materials like wood, bamboos, palmyra palms, reeds, leaves and grasses have been the oldest materials used by human beings. Although with the rapid pace of industrialisation, specially in several western countries, wood began to be replaced with alternative materials like cement, steel etc. yet its use has not vanished even in highly developed countries. Some of the reasons for thi...
V R Sonti, B Chatterjee
Changes in some important mechanical and physical properties of untreated and treated mining timber after exposure to the conditions of a colliery
1996 - IRG/WP 96-20082
Each of salt treated and untreated mining timber (wedge) pairs with 5x15 cm² cross-section and 155 cm length prepared from Scots pine, Bornmüller's fir and oriental beech was cut in the small standard test specimens to determine changes in some important mechanical and physical properties, 13 month after exposure to the conditions of Kozlu Hard Coal Mines in the depth of 52 m. Thus, the...
A Bobat
Bending strength of heat-treated spruce and pine timber
2002 - IRG/WP 02-40242
Heat-treatment of spruce (Picea abies) and pine (Pinus sylvestris) beams (45 x 145 mm) gave a reduction in bending strength of approximately 50%. The bending stiffness (modulus of elasticity) only decreased by 3.5%. Tests were carried out according to EN 408. Another effect of the heat-treatment was increased variation in bending strength. The 5th percentile value of the bending strength, the so c...
C Bengtsson, J Jermer, F Brem
Evaluation of a laboratory soft rot test on basis of weight loss and residual strength
1989 - IRG/WP 2336
Based on the principles of different previously reported experimental procedures dealing with laboratory soft rot testing, a study was conducted on treated poplar and beech. Preservatives used were CCA, CCF, AAC, Azaconazole and TCMTB. Treated samples were exposed for three months in a vermiculite substrate to Chaetomium globosum. Evaluation was based on absolute mass loss, percentage weight loss ...
W Verbeke, J Van Acker, M Stevens
Information from the COIPM wood group. (With Appendix: Préserver les matériaux en milieu marin sauvegarder l'environment marin telles sont la vocation et la mission du C.O.I.P.M.)
1989 - IRG/WP 4156
During the last COIPM Meeting, up to date information on cooperative work to test the resistance of plastic wrapping for pilings were submitted and discussed. In 1986 untreated wood samples wrapped with shrinkable polyolefin sleeves were submerged in 9 stations, situated in temperate and tropical waters. After 1 or 2 years of immersion the samples showed no sign of penetration by marine borers and...
A Gambetta
The degradation of wood surfaces by dilute acids
1985 - IRG/WP 3326
Thin radial/longitudinal sections(~100 µ) of Corsican Pine (Pinus nigra) and Lime (Tilia vulgaris), were exposed to Sulphuric, Sulphurous, nitric, acetic, and formic acid at 40°C in the pH range 2-6. After about 3 months exposure to Sulphuric, nitric, acetic and formic acid at pH 2.0 Pine lost some 20-25% of its tensile strength. Losses in tensile strength due to sulphurous acid were greater bei...
P D Evans, W B Banks
Determination of toxicity data for preservatives against Basidiomycetes by measuring the reduction in compression strength of wood
1988 - IRG/WP 2297
Blocks of Pinus radiata D. Don were treated to 12 retention levels with CCA and NaPCP. These were exposed for 12 weeks in agar jars to the dry rot (brown rot) Serpula lacrymans (Schum. ex Fr.) S.F. Gray. After mass loss determination, the same blocks were tested for reduction in compression strength parallel to the grain. Using both these parameters, together with interpolated 6 week strength loss...
J Wazny, J D Thornton
The resistance of timbers to impregnation with wood preservatives
1979 - IRG/WP 3137
It is anatomical structure which determines liquid flow rate within different timber species. This cannot be deduced from properties such as density or rate of growth, and can only be found by experiment. A standard test has been in use at the Princes Risborough Laboratory for many years, employing a pressure-impregnation treatment, and a large number of timbers have been studied. The test consist...
Anonymous
Glue-line additives for protecting plywood. A review
1978 - IRG/WP 2102
The conclusions of this review are: 1) Insecticidal glue-line additives can be used satisfactorily to protect plywood against insect attack. 2) It is uncertain, in spite of some claims, wether fungicidal glue-line additives can be similarly used to protect plywood against fungi under damp conditiones. There is a need for further work to validate the mycological tests that may be used to investigat...
R Cockcroft
The effect of oil-borne preservative treatments on the shear strength of FRP/wood composite adhesive bonds
2003 - IRG/WP 03-40265
Reinforcement of structural wood components with Fiber Reinforced Polymer (FRP) will enhance the beam’s strength, but actual data on long-term durability is sparse, not well documented or not readily accessible. In this study, bond properties of FRP-wood composite materials were investigated following treatment with creosote or copper naphthenate preservatives. The properties investigated inclu...
B Herzog, B Goodell, R Lopez-Anido
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
Diagnostics methods and routes proposalsto define selective sorting of demolition wood wastes
2001 - IRG/WP 01-50177
Wood wastes are more and more often used in different wood waste valorisation industries (panels, wood energy, cement factories, ...). These industries are in progress to include in their processes, wood wastes coming from demolition wood. A state of the art and an analysis have been made to propose : (1) diagnostics methods to carry out a classification of wood wastes on demolition sites and in t...
G Labat, E Bucket, C Fréret, G Deroubaix
Safe handling of solvents in relation to classification and labelling
1990 - IRG/WP 3569
The classification and labelling of chemical products, safety data sheets and personal protective equipment are topics which at present are given a very high priority in Denmark. The area is very large and may seem extremely difficult to comprehend. The frequent publication of acts and announcements from the authorities does not make the work any easier. In the following I will try explain how we ...
J Haugaard
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
Regulations of wood preservatives in Finland
1978 - IRG/WP 3124
Toxic wood preservatives are covered by the Poison Act (No. 309/69). The act came into force in May 1969 and was supplemented by the Statute on Poisons (No. 612/69). The act and the statute contain the regulations on the production, commerce and handling of poisons. Already when issued they were complained to contain some defects and obscurities. However, only minor alteration in them have been ma...
T Vihavainen
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
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