Your search resulted in 96 documents. Displaying 25 entries per page.
Natural progression of decay in unrestrained, Southern pine sapwood exposed above ground
1995 - IRG/WP 95-20060
In this study, the natural progression of decay is being monitored in 2.4-m (8-ft) lengths of dimension lumber. The 2.4-m lengths are supported without restraint in a horizontal plane approximately 0.75 m above ground in a partially shaded field plot in southern Mississippi. The lumber is 100% sapwood. Prior to installation in the field, each piece was planed to exactly 38 by 89 mm² (1.5 by 3.5 i...
R C De Groot, R J Ross, W Nelson
The influence of the location of a wood defect on the modulus of elasticity determination in wood durability testing
2004 - IRG/WP 04-20287
This study investigates the influence of the location of a wood failure in stakes upon elastic changes observed in beech specimens with the resonance vibration technique. Natural failures were simulated by artificially created defects at different locations of the test stake. The results indicate that the location of an attack in a stake is important for the measurement outcome. When the attack is...
L Machek, H Militz
In-ground field test of scots pine (Pinus sylvestris L.) sapwood and heartwood
2004 - IRG/WP 04-30336
Scots pine (Pinus sylvestris L.) sapwood and heartwood stakes treated with CCA-C and creosote were tested for one- year in a field plot in Bartın region in Turkey.
Scots pine heartwood stakes had lower preservative retention than sapwood stakes. Bending strength of the stakes was decreased after impregnation and one-year field test. While the bending strength of untreated sapwood was 93....
H Sivrikaya, H Hafizoglu
Non-destructive stress wave measurement of decay and termite attack in experimental wood units
1986 - IRG/WP 2256
The purpose of this study was to determine if stress wave analysis could be used to monitor the degradation of wood specimens exposed to the brown-rot decay fungi (Gloeophyllum trabeum) and of wood specimens subjected to attack by subterranean termites. One hundred fifty 3/4 by 3/4 by 12 in. Southern pine specimens were used for exposure to brown-rot decay fungi and two hundred twenty-five 3/4 by ...
R F Pellerin, R C De Groot, G R Esenther
Laboratory testing of wood natural durability - In soil-bed assays
1998 - IRG/WP 98-20141
Laboratory methods for assessing wood decay resistance are being investigated in the framework of an ongoing European research project. This paper summarizes the main results obtained for soil-bed tests based on the European prestandard ENV 807-Test 2. The data suggest that this testing methodology is suitable for evaluating the natural durability of timber species in soil-contact under conditions...
R Sierra-Alvarez, I Le Bayon, J K Carey, I Stephan, J Van Acker, M Grinda, G Kleist, H Militz, R-D Peek
Effect of vapour boron treatment on mechanical properties of wood based board materials
1992 - IRG/WP 92-3727
The mechanical properties of Medium density fibre board, Chipboard and Oriented strand board were investigated after treatment to two retention levels of boric acid applied as a vapour phase system. A range of mechanical properties were investigated. The vapour boron treatment does not have any significant effect on most of the mechanical properties of the boards. The exception is a reduction in i...
R Hashim, D J Dickinson, R J Murphy, J Dinwoodie
Resistance to decay of particle boards: Presentation of a test method
1986 - IRG/WP 2260
The experimentations were undertaken on particle boards 35 and 50 mm thick. The rot resistance tests were carried out on specimens whose dimensions were 600 x 75 x 35 mm³ for particle boards 35 mm thick and 800 x 75 x 50 mm³ for particle boards 50 mm thick according to a method derived from the one described in the documents IRG/WP/2214 and IRG/WP/2243. Two exposure periods were used: 12 and 16 ...
G R Y Déon, N Trong
An attempt to grow dry rot fungus Serpula lacrymans on mortar substrate in non-sterile conditions
1989 - IRG/WP 1385
According to many experts, Serpula lacrymans is probably the most dangerous wood destroying fungus in houses. Investigations of KOCH, A.P. (2) showed that incidence of this fungus in percent was around 20% when the frequency of some other standard fungi was far below (Coriolus versicolor: 0.2% for example). The work presented here is a part of a program carried out at CTFT for assessing the resist...
L N Trong
Residual resistance in eucalypt poles according to the degree of sanity
1984 - IRG/WP 2225
A lot of 50 eucalypt poles presenting external deterioration by fungus was taken from service and tested. These poles were classified into five degrees of sanity according to evaluation criteria adopted by the IPT Wood Division. After being classified, they were tested with respect to their bending resistance, in order to gather information about their critical degree of sanity which may define th...
F C Geraldo, S Milano, S G De Sequeira
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
Standardization of CCA treated 45 hardwood species grown in Bangladesh for REB crossarms
1995 - IRG/WP 95-20059
Researches on 45 hardwood species grown in Bangladesh regarding density, moduli of rupture (MOR), colour and treatability of sapwood and heartwood, seasoning property and natural durability of heartwood revealed that both sapwood and heartwood of 17 species could be full cell pressure treated with CCA at impregnation pressure of 14-18 kg/cm² and only sapwood of rest 28 species could be pressure t...
A K Lahiry
Bending properties of wood after its decay with Coniophora puteana and subsequent modification with selected chemicals
1999 - IRG/WP 99-40146
Mechanical properties of wood are often decreased due to decay processes caused by biotic and/or abiotic factors. Damaged wooden elements (e.g. historical structures) can be reinforced by more methods, including their modification with convenient chemicals. This paper presents influences of selected chemicals on basic bending properties (modulus of elasticity - MOE, modulus of rupture - MOR) of so...
L Reinprecht, S Varinska
Study of modulus of rupture, circumference taper, sapwood thickness and CCA treatment of Norwegian origin Pinus sylvestris poles
1994 - IRG/WP 94-20054
Nondestructive strength testing with Pilodyn (6J) of Norwegian Pinus sylvestris poles revealed effective modulus of rupture (MOR) of 54.39 N/mm² at wet conditions after CCA-C treatment and circumference measurement revealed circumference taper of 0.021 m/n. Sapwood thickness or penetration of CCA-C study revealed that 77% poles were with sapwood thickness equivalent to 39.6% of radius of poles an...
A K Lahiry, S Begum, G N M Ilias, M A B Fakir, R U Hafiz
Effect of post-treatment drying schedule on the modulus of elasticity of CCA-treated southern pine dimension stock using nondestructive methods
1987 - IRG/WP 3413
This paper describes the results from the nondestructive testing for modulus of elasticity (MOE) of southern pine (Pinus sp.) 2 x 6's treated with chromated copper arsenate and redried using three commercial kiln schedules. The data indicate that redrying CCA-treated southern pine dimension stock treated to above-ground retentions (4 kg/m³) has no deleterious effect on the MOE, regardles...
H M Barnes, S Moore
Durability of Wood/Plastic Composites Made From Parthenium species
2002 - IRG/WP 02-40225
Previous study indicated that the natural chemical constituents of the guayule plant (Parthenium argentatum) improved some durability properties of wood when it was treated with resin extracted from guayule. At present, there are about a dozen species of Parthenium growing in the North American continent. P. argentatum is the only species with harvestable amounts of the rubber latex. Other specie...
P Chow, F S Nakayama , J A Youngquist, J H Muehl, A M Krzysik
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
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
Influence of the content of organic matter of soil on the degradation of wood by soft rot fungi
1970 - IRG/WP 27
The degradation of wood specimen burried in the soil by soft rot fungi is influenced by a number of factors. These are in particular the water holding capacity, water content, content of organic matter, pH, content of mineral nutritive substances etc. The results of the interlaboratory tests, carried out within the IRG/WP let presume that the intensity of wood degradation occurs proportionally inv...
O Wälchli
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
Resistance of board materials against fungal decay: A comparative experiment on Kolle flask tests method and direct test method
1985 - IRG/WP 2243
Two sets of plywood (Aucoumea klaineana Pierre) 7 and 11 ply, treated by two preservatives, and untreated, were tested by two methods: 1. Kolle flask test method on malt-agar substrate according to the French standard NF B 51.295; 2. A direct test method in non sterile conditions according to DocNo: IRG/WP/2214. The exposure time far both methods was 12 weeks. After exposure, the degree of attack ...
G R Y Déon, L N Trong
Some Experiences with Stake Tests at BAM Test Fields and in the BAM Fungus Cellar
Part 1: Comparison of Results of Visual Assessments and Determinations of Static Moduli of Elasticity (MOE)
2005 - IRG/WP 05-20319
With examples of routine in-ground stake tests differences are shown in the performance of wood preservatives at the BAM test fields Lehre and Horstwalde and in the BAM fungus cellar. Signs of attack of micro-organisms were assessed visually according to EN 252. Periodical determinations of static moduli of elasticity (MOE) revealed the influence of the attack on the elastic properties of the wood...
M Grinda, S Göller
Moisture correction for ultrasonic MOE measurements above fibre saturation point in Scots pine sapwood
2006 - IRG/WP 06-20333
There is a high correlation between methods for dynamic modulus of elasticity (MOEdyn) and static modulus of elasticity (MOEstat). MOEdyn methods have been found sensitive to detect early stages of decay and may be seen as an option for non-destructive wood durability testing. As the MOEstat measurements do not change after reaching the fibre saturation point, the uncorrected MOEdyn data from ultr...
E Larnøy, G Alfredsen, H Militz
Effect of wood decay on the proportional limit of thin wood samples stressed in the bending mode
2006 - IRG/WP 06-20334
When using bending stiffness as a measure of wood decay it is advantageous to repeatedly test individual samples after they are exposed to decay fungi for varying periods of time. In order to obtain reliable results, variation in modulus of elasticity (MOE) values of the test samples that are repeatable bent to a given deflection must be considered. In this study it was shown that sound 3mm thick ...
G Li, D Nicholas, T Schultz
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
Natural durability of different wood species in above ground applications - Weight and MOE loss
2008 - IRG/WP 08-10667
In Norway, exterior wood structures have traditionally, nearly exclusively been made of untreated Norway spruce (Picea abies (L.) Karst) and pressure treated Scots pine (Pinus sylvestris L.). In recent years there has been a tendency that other wood species, like various Norwegian hardwoods or imported species, have been used in exterior above ground applications, often not surface treated. For se...
F G Evans, P-O Flæte, G Alfredsen