Your search resulted in 468 documents. Displaying 25 entries per page.
The potential and the challenges of acetylated wood in timber bridges - experiences from an ongoing project
2017 - IRG/WP 17-40792
Acetylated wood is known to be a durable and dimensional stable alternative for high performance materials, and has high potential for exterior timber structures. Research has shown that acetylated wood can be effectively bonded by various adhesive types. However, one of the most common used adhesives for timber constructions, Melamine Urea Formaldehyde (MUF), shows a high degree of delamination o...
A Treu, R Bredesen, F Bongers
Plasma-assisted bleaching of blue-stain from lodgepole pine wood
2017 - IRG/WP 17-40799
We hypothesize that plasma will etch wood and fungal hyphae in blue-stained lodgepole pine, and increase the ability of hypochlorite bleach to remove discolouration from blue-stained wood. Blue-stained lodgepole pine wood was exposed to a glow-discharge plasma derived from water, and the surface wettability, permeability and colour of the treated wood was measured. Plasma-treated wood was dipped i...
A Jamali, P D Evans
A summary of history and use of timber bridges in New Zealand
2017 - IRG/WP 17-40801
Wooden bridges have been an important part of road and rail networks in New Zealand. While wooden structures have largely been replaced by concrete and steel on major arteries they still have a place where lightweight, easily assembled structures are needed. These timber bridges may also be a cheaper alternative to other materials in roads which carry relatively low traffic loads. In the last ten ...
D Page, T Singh
Penetration behaviour of different hydrophobic carrier substances for oily wood preservatives in Beech and Scots pine sapwood
2017 - IRG/WP 17-40804
The use of creosote as a wood preservative has a long history. Current areas of application are railway sleepers, transmission poles, timber bridges and marine applications. If the approval for creosote will not be prolonged, alternative wood preservatives will be needed. As the penetration behaviour after pressure impregnation of different alternative oily products in this fields of application i...
M Starck, A Gellerich, H Militz
Decay resistance of beams made from thermally modified Scots pine and Norway spruce after 6 years’ exposure in ground contact
2017 - IRG/WP 17-40806
In the present study the resistance of beams treated by ThermoWood® process was studied in ground contact and the results given are based on a “modified” EN 252 test. After six years’ exposure clear differences were found between untreated Scots pine and Norway spruce beams and treated ones. In all cases thermal modification improved the performance. Thermally modified pine heartwood showed...
S Metsä-Kortelainen, H Viitanen
Multivariate modeling of mould growth in relation to extractives in dried Scots pine sapwood
2017 - IRG/WP 17-20629
Influence of extractives on mould growth on Scots pine sapwood dried in air or in kiln was studied. Boards were sprayed with water mixtures of spores of the fungal species Penicillium sp., Aspergillus sp., Mucor sp., Paecilomyces sp., Trichoderma sp., treated at a temperature of 22ºC at 90% RH, classified into a percentage of covered area. Acetone and water extracts were isolated and analyzed for...
O Karlsson, O Myronycheva, M Sehlstedt-Persson, M Öhman, D Sandberg
Impact of sapwood portions on the durability of adjacent heartwood of Pinus sylvestris, Pseudotsuga menziesii and Quercus robur. Part 1: Laboratory studies
2018 - IRG/WP 18-10922
Sapwood is generally considered as non-durable and assigned to durability class DC 5 according to European standards independent from the wood species. It is commonly agreed that sapwood decays faster than adjacent heartwood, but it is controversially discussed whether sapwood serves as feeder material and thus accelerates onset and progress of decay in more durable heartwood or decays independent...
C Brischke, P Homann, A Gellerich
Material Resistance and Chemical Composition of Italian Stone Pine (Pinus pinea)
2018 - RG/WP 18-20645
Relevant properties of stone pine (Pinus pinea) wood have been only fragmentarily addressed in the past, which has been recognized as a limiting factor for its potential applications. The amount of the respective wood species on the market will likely increase in the future. The sorption properties, permeability to water, extractives content and durability against fungi of Pinus pinea sapwood and ...
M Humar, M De Angelis, M Romagnoli, V Vek, I Poljanšek, P Oven, N Thaler, B Lesar, D Kržišnik
An examination of the potential for the use of the Maillard reaction to modify wood
2018 - IRG/WP 18-40829
Finding efficient ways to decrease wood decay caused by fungi and increasing its dimensional stability is an important issue in the timber construction. A possible way to avoid wood decay by fungi is by reducing the water content of wood, since water is a primary condition for fungal growth. Bulking of the wood cell wall by chemical reagents occupies the space where water normally occurs. At the s...
K Peeters, E Larnøy, A Kutnar, Č Tavzes, C A S Hill
Thermally modified timber treated with methacrylate
2018 - IRG/WP 18-40849
Thermally modified timber (TMT) from Scots pine sapwood similar to Thermo-D quality was impregnated with methacrylate resin by the hot-and-cold method and subsequently cured at elevated temperatures. The results showed that methacrylate resin could be used to reduce colouring of painted TMT wood during accelerated weathering probably by hindering the migration of extractives. The resin itself did ...
O Karlsson, O Myronycheva, DJones, D Elustondo, D Sandberg
Performance of untreated timbers in above ground decking tests: Preliminary results from an international collaborative trial
2019 - IRG/WP 19-10940
The ability to accurately predict wood decay risks under varying environmental conditions has long been of interest to timber users. Accurate predictions are difficult owing to the myriad of variables associated with the decay process including wood species, wood inhabiting organisms, timber building element design and environmental conditions. Despite these difficulties, decay predictions have be...
L P Francis, J Norton, E Melcher, A H H Wong, J Kok Lai, M Klamer, M J Konkler, J J. Morrell
Accumulation of copper in parenchyma cells in southern pine wood treated with micronized and amine-copper preservatives
2019 - IRG/WP 19-20657
Our previous research used X-ray micro-computed tomography to examine the micro-distribution of copper in southern pine wood treated with a micronized wood preservative (MCA) and an amine-copper preservative (ACQ). We found that copper in wood treated with MCA was mainly concentrated in fusiform rays (rays containing resin canals), and in vertical (axial) resin canals. A similar, although not iden...
D Feng, M L Turner, A Limaye, M A Knackstedt, P D Evans
Efficacy of microwave treatments against Pine Wood Nematode
2019 - IRG/WP 19-20658
The pine wood nematode Bursaphelenchus xylophilus (Steiner and Buhrer) Nickle (PWN) is the causal agent of “Pine wilt disease” affecting coniferous forests, and since its detection in 1999 in Portugal, has obliged the European Union to take action to prevent its spread (Decision 2006/133/CE). One of the main measures applied is the International Standard for Phytosanitary Measures ISPM No. 15 ...
L Robertson, M T Troya, F Llinares, J C Cabrero
Chemical Analysis of Southern Pine Pole Stubs Sixty Months Following Treatment with a Methylisothiocyanate-Based Solid Fumigant Stick
2019 - IRG/WP 19-30740
Methylisothiocyanate-based fumigants have been commercially used in the United States for over 35 years to control internal decay in utility poles and other wooden structures with little technological advancement. The most recently commercialized methylisothiocyanate-based fumigant is chemically known as dazomet. Dazomet is a free-flowing powder or granule that decomposes in the presence of mois...
D J Herdman, T Pope, R R Browning
The development of a suitable fire retardant for Radiata pine and other species
2019 - IRG/WP 19-30744
The use of fire retardant chemicals, with the overarching aim of creating a safer environment is not a new one, however it is generally under-developed and is often afflicted with an image of environmental and health issues and misperceived high costs. There is an ever-increasing need and desire for effective fire retardancy in timbers to inhibit or suppress the combustion process. This is paramou...
B R Derham, M R Fortune
The anti-weathering mechanism of extractives in thermally modified Scots pine
2019 - IRG/WP 19-40880
Results from the electron spin-resonance spectroscopy (ESR) analysis indicated that thermally modification of wood can inhibit the generation of phenoxyl radicals during UV irradiation and consequently lead to the increase of the color stability of wood. In order to clarify the evolution and role of extractives in thermally modified wood during the process of weathering, the compositions of aceton...
H Shen, J Cao
Terrestrial laser scanning (TLS) – a potential tool for improved utilisation of the natural durability of Scots pine for solid wood products
2019 - IRG/WP 19-50358
The natural durability of sapwood of most species is generally low, while heartwood can be more resistant to biodeterioration. For the sawmill industry various lumber products require certain diameters and lengths of the logs in addition to requirements for wood properties. When utilising the heartwood, it is therefore important to acquire information already in the forest about which trees that c...
P-O Flaete
Different levels of acetylation lead to groupwise upregulation of non-enzymatic wood degradation genes of Rhodonia placenta during initial brown-rot decay
2020 - IRG/WP 20-10958
Rhodonia placenta, often used as a model fungus to represent brown rot fungi, uses a two-stepped degradation mechanism to degrade wood. Regarding the overcoming of wood protection systems the initial degradation phase seems to be the crucial point. A new laboratory test enables the separation of the non-enzymatic oxidative and the enzymatic degradation phases, which has previously been proven chal...
M Kölle, R Ringman, A Pilgård
Effect of long-term immersion in fresh and salt water on mould growth on Scots pine (Pinus Sylvestris L.) wood
2020 - IRG/WP 20-10962
Wood exposed outdoors will eventually be degraded by fungi, depending on exposure and material characteristics. Numerous wooden constructions in the Røros municipality have existed since the 17th century, but wood used in recent repairs have decayed faster than expected. Before 1970 timber was mainly transported by log driving or rafting, and the logs were immersed in water for longer or shorter ...
M Sand Austigard, J Mattsson
Profiling fungal degradation of Scots pine sapwood by short wave infrared hyperspectral image analysis
2020 - IRG/WP 20-20667
Hyperspectral image analysis of Scots pine sapwood wood affected by decay fungi has been carried out as part of a Ph.D. thesis within the project Remote Inspection of Wooden Utility Poles (RIWUP).
In a lab experiment, Petri-dishes with Scots pine sapwood samples on malt agar medium were infected with two types of decay fungi, a brown rot and a white rot. The wood samples were scanned with a HySpe...
A Jochemsen, G Alfredsen, I Burud
Yellow birch fire-protection using polyelectrolytes complexes
2020 - IRG/WP 20-30755
Fire protection has been a major challenge in wood construction for many years. The demand for high-performance, environmentally friendly treatments respecting the physical and chemical characteristics of the material has been accentuated in recent years. Halogenated fire-retardant (FR) compounds were commonly used from the 70’s for their low-cost and high efficiency. They are able to form radic...
M Soula, F Samyn, S Duquesne, V Landry
Investigations into the use of Maleic Anhydride/Sodium Hypophosphite as a Wood Modification Process
2020 - IRG/WP 20-40891
The formation of crosslinked bonds between wood constituents is believed to be an effective way to stabilize wood against wet conditions. The possibility to use maleic anhydride (MA) combined with sodium hypophosphite (SHP) as crosslinking agents was studied, using Scots pine sapwood and a model compound. The modified wood showed weight gain and bulking effect after treatment and subsequent Soxhle...
I Kim, D Jones, O Karlsson, D Sandberg, O N Antzutkin, F Ullah Shah
Monitoring uptake and penetration of pesticides during impregnation of pine (Pinus sylvestris) and spruce (Picea abies) wood with bio-based microemulsion gel formulations
2020 - IRG/WP 20-30756
Even in dry state wood is susceptible to biological degradation. Preservation against biological decay in exposed conditions is conventionally achieved by impregnating the wood with pesticides applied at professional and industrial levels. Impregnation of wood with preservatives is a complex process that involves wood macro- and microstructure, and the physical characteristics of woods. Here we fo...
D Messaoudi, K Ruel, J-P Joseleau
Durability of acetylated Radiata pine: Laboratory tests and performance in practice
2020 - IRG/WP 20-40899
Wood acetylation is an established process to enhance biological durability and dimensional stability of lower valuable wood species without the use of biocides. Acetylated Radiata pine (ACCOYA® wood) has been on the market for more than 10 years now, starting in 2007.
Numerous lab tests have confirmed the high durability of acetylated Radiata pine. Here, additional data with four Radiata pine ...
K Jacobs, W Scheiding, B Weiß
Sterilization of Large Timbers during Preservative Treatment: How Quickly We Forget
2020 - IRG/WP 20-40902
Air seasoning is a common method of moisture management in utility poles and is done de facto during pole storage prior to treatment. However, extended air drying prior to treatment encourages fungal attack and can facilitate establishment of decay fungi in poles before a protective preservative barrier is applied. This problem can be mitigated by proper air-seasoning methods coupled with heat ste...
G Presley, J Cappellazzi, M Konkler, K Maguire, R Nelson, J J Morrell