Your search resulted in 187 documents. Displaying 25 entries per page.
L-joint based testing for service life prediction of exterior plywood in out of ground contact conditions
2006 - IRG/WP 06-20342
Good biological performance of several plywood types in exterior conditions is most probably related to altered wood moisture behaviour compared to solid wood. Therefore a test set up was developed, using EN 330 L-joint testing methodology, to facilitate differentiation of plywood for exterior applications.
The proposed test set up is an adaptation of an accelerated L-joint method introduced by V...
J De Smet, I De Windt, J Van Acker
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
Wood-Plastic Composites and the Durability Dilemma: Observations from the Field
2006 - IRG/WP 06-40351
Wood-Plastic Composites (WPCs) used for decking, window & door moldings have experienced dramatic growth in North America over the last several years, with annual production increasing at rates greater than 20% per annum since 1998. A key factor contributing to this growth has been the successfully communicated message that they are "virtually maintenance free". The common perception being t...
M J Manning, F M Ascherl, M E Mankowski
Photo-degradation of modified and non-modified wood, coated with water borne acrylic coatings during artificial light exposure
2007 - IRG/WP 07-30416
A series of experiments were carried out to investigate photo-degradation of thermally modified (at 210oC and – 0.9 bars for two hours) and non-modified spruce wood (Picea abies L (Karst)), coated with transparent and semitransparent (with 3% pigment content) acrylic coatings during artificial UV light irradiation for 200 hours. Photo-degradation was evaluated in terms of colour changes througho...
M Deka, M Tomažic, M Petric
Micro- and hydro-sandblasting for wood and wood coatings
2007 - IRG/WP 07-40380
Exterior wood coatings are getting increasingly durable and often more film forming. As a result they become difficult to renovate. Conventional renovation techniques (chemical or thermal stripping, sanding) are demanding techniques which take a long time to implement. Therefore renovation techniques are requested which are easier to use and which ensure that the wood surface is suitable for a re-...
L Podgorski, V Georges, P Svane
Natural Weathering of Coated Oil Heat Treated Wood
2007 - IRG/WP 07-30440
Oil heat-treated (thermally modified) pine wood was coated with 9 different types of solvent- or water-borne exterior finishes. The systems with modified wood substrate as well as unpainted and painted non-modified controls were exposed to weathering (EN 927-3) on two locations with sub-alpine and alpine climate. The influence of natural ageing on surface systems was evaluated after one year of ex...
M Petric, B Kricej, M Pavlic, A Rapp
The Effect of Solar Radiation on the Surface Checking of Wood
2007 - IRG/WP 07-40356
The aim of this research was to investigate whether exposure to solar radiation increases the checking of wood exposed to the weather, and examine the causes and spectral dependency of such an effect. Lodgepole pine samples were exposed outdoors under filters which transmitted selected regions of the solar spectrum while allowing other weathering factors to act on samples. Surface checking in samp...
P Evans, K Urban
Anatomical, physical and chemical changes of Bamboo (Phyllostachys puberscence ) during weathering processes
2008 - IRG/WP 08-10650
Bamboo (Phyllostachys puberscence) culms with 1, 2, 3 year old were exposed to natural weathering condition in Gwangju, Korea for 12 months. Changes in color, surface topography, strength and chemical properties were investigated using various microscopic and instrumental techniques. After one year’s weathering, the color of bamboo became lighter but strengths of bamboo did not change significan...
Jong Sik Kim, Kwang Ho Lee, Mi Young Cha, Yoon Soo Kim
Relationship between coating properties and their performance on treated wooden decks
2008 - IRG/WP 08-30454
Preservative treated wood benefits from the application of a surface coating to protect it from weathering (UV and rain). Different preservative formulations may affect surface properties of treated wood differently; therefore compatibility of coatings with different preservative treated wood types should be considered. This paper examines coatings characteristics and their weathering performance ...
M Ahmadinejad, P A Cooper
Service life prediction of wood: scale-dependent tools within a bio-engineering framework
2008 - IRG/WP 08-20387
Service life prediction (SLP) is a complex yet essential method for the building industry. Accurate and precise assessment of the components is crucial for a strong position of wood on the market. As it is a biological material, wood has an inherent variability and is susceptible to fungal attack. Therefore a profound knowledge of these characteristics is the corner stone of SLP for wood products....
J Van den Bulcke, J Van Acker, M Stevens
Development of a Weatherometer to Accelerate the Surface Checking of Wood
2008 - IRG/WP 08-20388
There is significant interest in developing preservatives that are better at preventing wood from checking. Currently, however, there is no accepted test methodology for accelerating the development of checks in wood samples so information on the effectiveness of treatments at restricting checking can be obtained more quickly. This paper describes the development of a new type of weatherometer (Ac...
R Ratu, P D Evans
Bi-oleothermal treatment of wood at atmospheric pressure: resistance to fungi and insects, resistance to weathering and reaction to fire results
2008 - IRG/WP 08-40418
Bi-oleothermal process is a simple treatment which has been developped by CIRAD in cooperation with FCBA. It allows a deep impregnation of wood with hydrophobic products using cheap facilities. The process includes two steps at atmospheric pressure. The first one is a dipping of wood samples in a hot oil bath (between 110 °C and 200°C) which creates an overpressure inside the wood. The second on...
L Podgorski, I Le Bayon, I Paulmier, J-D Lanvin, V Georges, D Grenier, H Baillères, J-M Méot
The Effects of Solar Radiation on the Fungal Colonization and Color of Weathered Wood
2008 - IRG/WP 08-10676
Solar radiation rapidly depolymerizes lignin at wood surfaces exposed outdoors producing a suite of low molecular weight aromatic compounds within weathered wood. Fungi colonizing weathered wood are able to metabolize these aromatic compounds, and many of them also contain high levels of melanin to protect themselves from the harmful effects of UV radiation. Both of these adaptations suggest that ...
V Hernandez, C Breuil, P D Evans
Accelerated weathering of nine tropical wood species from Cameroon
2009 - IRG/WP 09-10705
The natural durability of tropical species for building components has been a subject of recent concern and questioning, mainly the resistance to weathering. Weathering resistance of nine tropical species from Cameroon, namely Azobe, Bilinga, Bubinga, Teak, Dousie, Moabi, Musanga, Sipo and Padauk were evaluated using an accelerated weatherometer for 2016 hours. Measurement of moisture fluctuation,...
S Pankras, Jinzhen Cao, D P Kamdem
Component leaching from CCA, ACQ and a micronized copper quat (MCQ) system as affected by leaching protocol
2009 - IRG/WP 09-50261
Leaching results for Cu, Cr and As (CCA) and Cu (ACQ and MCQ) from southern pine are compared for laboratory tests (AWPA E11, and draft OECD methods I and II) and natural weathering of horizontally and vertically oriented lumber samples over two seasons. This paper expands on results and comparison of results presented at the IRG regional meeting in Costa Rica in Dec 2008 (Cooper and Ung 2008) a...
P A Cooper, Y T Ung
Weathering of Wood Modified with the N-Methylol Compound 1,3‑dimethylol-4,5-dihydroxyethyleneurea (DMDHEU)
2009 - IRG/WP 09-40467
Scots pine (Pinus sylvestris L.) sapwood boards were treated with a methylated 1,3‑dimethylol-4,5-dihydroxyethyleneurea (mDMDHEU) causing weight gains of approx. 25% and exposed to weathering for 18 months. Compared to untreated boards, treatment with mDMDHEU reduced surface discoloration mainly caused by staining fungi. Boards treated with mDMDHEU exhibited clearly lower moisture content th...
C Mai, Yanjun Xie, A Krause, K Urban, P D Evans, K Richter, H Militz
A fast and economic method to produce grey wooden surfaces for decking and cladding: preliminary results
2009 - IRG/WP 09-40474
Uncoated wood is commonly used in France for cladding and decking to minimise maintenance. However wood surfaces progressively turn grey due to exposure to sunlight and water. This grey colour develops after several months depending on the wood species and the exposure: in the northern hemisphere surfaces facing south and west are most exposed and turn grey more rapidly than those facing north and...
L Podgorski, V Georges, I Garmendia, B Sánchez Sarachu
Early detection of colonisation by blue stain and mould on modified wood using PCR technique
2010 - IRG/WP 10-10730
The aim of this research was the early detection of fungal attack on the surfaces of modified and unmodified wood after natural weathering. The investigation was carried out by molecular techniques and the development and establishment of genus/species specific PCR for important moulds and sapstain fungi was part of this work. After adaption of the method, a monitoring of the succession of Ascomyc...
A Steitz, B Schmöllerl, N Pfabigan, S Bollmus, G Grüll
The Use of Micro-Tensile Testing to Assess Weathering Decay and Oxidative Degradation of Wooden Items
2010 - IRG/WP 10-20433
This paper presents a method to study the weathering performance of wooden items and to assess the oxidative degradation of wood via the Fenton reaction. Weathering resistance and photo-stability of wood was tested using pine wood (Pinus sylvestris) veneer strips measuring approximately 60 µm in thickness. The veneer strips were treated using a reactive chemical to impart surface protection. The ...
C Mai, Yanjun Xie, Zefang Xiao, P D Evans, H Militz
Finite Element Modelling of the Checking of Wood Exposed to Accelerated Weathering
2010 - IRG/WP 10-20459
The surface checking that develops when wood is exposed to the weather reduces the visual appeal of treated wood products and can reduce the effectiveness of preservative treatments. There is strong interest in developing solutions to this problem and also a growing realization that such solutions may evolve from a deeper understanding of the mechanisms responsible for surface checking. In this pa...
S G Ribarits, P D Evans
Photostabilization of Wood with Higher Molecular Weight UV Absorbers
2010 - IRG/WP 10-30524
Higher molecular weight UV absorbers were created by reacting the epoxy-functionalized UV absorber 2-hydroxy-4(2,3-epoxypropoxy)-benzophenone (HEPBP) with maleic, phthalic or succinic anhydride. The ability of the UV absorbers to photostabilize wood was then examined. FTIR-spectroscopy confirmed that HEPBP reacted with phthalic anhydride to create a polyester that preserved the UV-absorbing benzop...
P D Evans, M J Chowdhury
Distribution and availability of preservative components in ACQ treated wood - effects of coatings and weathering
2010 - IRG/WP 10-30537
Copper and quaternary ammonium compound (quat) distributions across lumber (gradients) and availability, as measured by amount removed by intensive leaching of wood flour, were measured in ACQ treated southern pine lumber. Samples were evaluated just after treatment and stabilization, or after 3 years of laboratory storage, or after 3 years of natural weathering exposure. The objective was to in...
T Ung, M Nejad, P Cooper
The Effects of Natural Weathering on the Properties of Heat Treated Alder Wood
2010 - IRG/WP 10-40484
Heat treatment is an effective method to improve the dimensional stability and biological durability of wood. The heat treatment technology and the heat treated wood products were recently introduced to Turkey. However, only a few studies have been reported on the effect of natural weathering on the properties of heat treated wood in both Turkey and the world. In this study, heat treated alder (Al...
S Yildiz, Ü C Yildiz, E D Tomak
Comparison of colour change in wood clear-coating systems including inorganic and organic UV absorbers for exterior use
2010 - IRG/WP 10-40499
The aim of this work is to compare the performance of inorganic and organic UV absorbers used in a wood coating application against weathering. Our study has investigated the colour changes of selected UV absorbers; hombitec 402 RM from the Sachtleben Company as an inorganic UV absorber, tinuvin 477 DW from the Ciba Company as an organic UV absorber. The study was carried out on two wood species; ...
Ö Özgenç, B Forsthuber, A Teischinger, C Hansmann
Impact of wood species on the performance of exterior wood coatings
2010 - IRG/WP 10-40519
To prolong the service life of a wooden construction the protective function of a coating is of utmost importance. The chemical composition as well as the wood-coating interface affects the performance of this protective layer and obviously wood species have an impact too. This paper discusses the influence of wood species on the overall coating performance. Therefore, a range of opaque waterborne...
I De Windt, J Van den Bulcke, J Van Acker