Your search resulted in 210 documents. Displaying 25 entries per page.
A critical view on early indicators for above ground field performance of wood
2013 - IRG/WP 13-20509
Above ground field tests are quite often a balancing act between the provision of realistic test conditions, reliable statistics, and acceptable long test durations. Within this study we therefore reviewed 543 data sets from above ground field tests performed at 36 different test sites in 8 countries in Australia and Europe. The main objective was to investigate possible correlations between early...
C Brischke, L Meyer, G Alfredsen, P-O Flæte, L Francis, M Hansson, P Larsson Brelid, J Jermer
Quasi-in-situ durability tests on oak timber bridges
2013 - IRG/WP 13-20510
This study aims on developing a method for determination of wood durability on samples taken from real structures in service. Therefore quasi-in-situ durability tests have been conducted exemplarily on timber bridges made from English oak (Quercus robur L.). Drilling cores were found to be a feasible alternative to standard specimens for laboratory durability tests against pure cultures of Basidio...
C Brischke, C J Behnen, M-T Lenz, K Brandt, E Melcher
Determination of the natural durability of solid wood against wood-destroying fungi - a European round-robin test
2013 - IRG/WP 13-20511
In Europe the durability of wood against wood-destroying basidiomycetes is tested according to CEN/TS 15083-1 (2005). Hitherto existing experience with this standard is quite heterogeneous and results from previous round-robin tests have stayed unreported or have been reported incompletely. In particular the need for natural pre-weathering of the test specimens to allow potential detoxification of...
C Brischke, C R Welzbacher, A Gellerich, S Bollmus, M Humar, K Plaschkies, W Scheiding, G Alfredsen, J Van Acker, I De Windt
Statistical analysis of durability tests - Part 2: Principles of time-to-failure and application on field test data
2013 - IRG/WP 13-20512
Service life prediction is an important topic in wood research, especially with regard to the Construction Products Regulation (CPR). Both laboratory tests as well as in-service performance testing is therefore essential, in combination with proper monitoring and analysis tools. A crucial concept is variability and the incorporation of variability in tests and analysis. In this paper we focus on t...
J Van den Bulcke, I De Windt, C Brischke, C R Welzbacher, A O Rapp, J Van Acker
Changes of fungicidal, mechanical and sorption properties of wood during above ground outdoor exposure
2013 - IRG/WP 13-20513
The aim of this preliminary study was to investigate differences in mechanical, fungicidal, and sorption properties of four different wood species (sweet chestnut (Castanea sativa), common beach (Fagus sylvatica), Norway spruce (Picea abies), and copper-ethanolamine (CuE) impregnated Norway spruce (Picea abies)) that were exposed in the 3rd use class (CEN, 1992) for periods between 4 and 30 months...
N Thaler, M Humar
The assessment by visual grading, change of color and ergosterol content ratings, the resistance to mould fungi of treated with wood preservative Scots pine sapwood
2013 - IRG/WP 13-20514
The filamentous (mould) fungi belonging to Ascomycetes, Deuteromycetes group are an cosmopolitan organisms which attacks wooden elements disfiguring them, dropping their value and causing environmental and health hazard. The fungi in a short time cause mainly disfigurement of wood does not effect on strength properties of wood, but with strong prolongation of duration of conditions favourable for ...
A Fojutowski, A Koziróg, A Kropacz
Service life evaluation of wood - an engineering approach
2013 - IRG/WP 13-20515
A performance-based service life design format based on climatic exposure on one hand and “biological wood resistance” on the other hand is presented in this paper. Important concepts are the introduction of limit states as well as reliable performance models for the biological processes, by which onset of deterioration can be predicted for arbitrary climate histories. Examples of applications...
S Thelandersson
Developing Analytical Methods for Determination of Quaternary Ammonium Compounds (DDAC) using HPLC and HPLC-MS (Application to treating solution and preservatives treated wood)
2013 - IRG/WP 13-20516
Korea preservative treating industry has mainly used alkaline copper quaternary (ACQ) expected over 80% of market share in Korea. ACQ employs dodecyl dimethyl ammonium chloride (DDAC) and benzyl dimethyl dodecyl ammonium chloride (DBAC) for active ingredient along with copper. The strongly increasing domestic applications for wood preservatives require developing accurate and reproducible analytic...
Sung-Mo Kang, Kwon-Min Kim, Won-Mo Koo, Myeong-Won Cho
Testing the performance of timber using 27 different field test methods
2013 - IRG/WP 13-20517
Numerous test methods to determine the durability of timber and timber products have been described in relevant literature. However, only some of these methods have been standardized and thus only very few are regularly used for resistance tests in the field. Since results from extensive comparative field studies have shown differences in moisture performance between different test methods, the ai...
L Meyer, C Brischke, J Rieken
Climatic impacts on the moisture performance of wooden decking and facades
2013 - IRG/WP 13-20518
In outdoor usage wood is exposed to a variety of influences, which reduce its durability against biological deterioration and wetting. Besides many other factors the service life of wooden facades and cladding is dominated by occurring moisture loads on the one hand and their capability to withstand moisture on the other hand. Hence, climatic factors have a direct impact on the material climate an...
T Bornemann, C Brischke, G Alfredsen
Image analysis for mould and sapstain detection on wood
2013 - IRG/WP 13-20519
Laboratory tests for mould growth on wood products are time consuming and rely on visual assessments of specimens utilizing subjective rating systems. Accelerated laboratory methods are needed that can provide rapid, quantitative assessment of mould and sapstain growth on solid and composite wood products. Image analysis of scanned spore imprints from southern pine or oriented strandboard (OSB) sp...
C A Clausen, V W Yang
Accelerated H3 above-ground decay testing
2013 - IRG/WP 13-20520
An above-ground H3 fungal field trial was installed at two sites in Australia and one in New Zealand, as well as in two Accelerated Field Simulators. The aim was to find a method that would shorten the time required for evaluating new preservatives and protection systems. One-quarter H3 retentions were installed, as first results suitable for registration occur when these reach 70% soundness. Twel...
L J Cookson, D Page, T Singh
Visual Inspection – How Important is the Influence of the Evaluator?
2013 - IRG/WP 13-20521
Visual inspection is often a crucial means of judging the efficacy and performance of a preservative. It is used in non-destructive testing in long term exposure trials or simply, when the practical use and precision of the human eye is a good means of measure. As for the procedure described in EN 252, the impression of softness due to decay of the wood has also to be considered. Although, a thumb...
M Klamer, P Larsson Brelid, I Stephan
Extraction and analysis of DNA from green and seasoned timber as basic methods for determination of wood species and origin
2013 - IRG/WP 13-20523
Against the background of the European timber trade regulation EUTR, commenced to law by March 2013, the determination of wood species and tracing of its origin is getting a great importance. A promising approach for establishing fast and reliable tracking systems for wood products is DNA analysis. A critical point is the extraction of analysable DNA from the wood and its lignified cell walls. Thu...
K Jacobs, H Mende, W Scheiding
Virulence of two Laboratory Test Strains and one Natural Isolate of Rhodonia (Oligoporus) placenta against Thermally Modified Pine and Beech Wood
2013 - IRG/WP 13-20524
Rhodonia (Oligoporus) placenta is known as a relative aggressive basidiomycete fungus against thermally modified timber. In durability lab tests, this often results in a lower durability class, compared to other test fungi. In the reported work, the virulence of three different strains of Rhodonia placenta for untreated and thermally modified timber was determined and compared. Therefore, two lab ...
K Plaschkies, W Scheiding, K Jacobs, N Rangno
Predicting the Rate of Decay, and the Potential for Misinterpretation of Proper Scientific Method
2013 - IRG/WP 13-20525
Predicting the rate of fungal attack in wood-based materials and its effect on properties remains the holy grail of wood products pathologists; however, achieving this goal is difficult because of the many variables associated with the process. This paper reviews some of the more important aspects of the decay process in relation to test methodology and then discusses how data are sometimes used b...
B S Goodell, J J Morrell
The activity of a wood-decaying fungus during drying and rewetting cycles measured by isothermal calorimetry
2013 - IRG/WP 13-20526
Wood decaying fungi are an essential part of any ecosystems as they are the main decomposers of cellulose and lignin-containing materials. But as wood is a common building material the risk for decay fungi growth and subsequent degradation of our construction material is a concern. There are important physiological aspects of the growth and activity of decay fungi that are unknown today, and witho...
S Johansson, L Wadsö, A Pilgård, G Alfredsen
Cell wall properties of softwood deteriorated by fungi: combined chemical analyses, FT-IR spectroscopy, nanoindentation and micromechanical modelling
2013 - IRG/WP 13-20527
Mechanical properties of wood are determined by its inherent hierarchical microstructure, starting at the nanometer scale, where the elementary components cellulose, hemicelluloses, and lignin build up the wood cell wall material. Fungi cause degradation and decomposition of these components and, thus, alter the mechanical properties of wood. The aim of this study is to gain new insight into these...
L Wagner, T K Bader, K de Borst, T Ters, K Fackler
What molecular biology can tell us about the biodegradation of lignocellulose: the utilization of molecular techniques for the detection, identification and enhanced understanding of wood degrading organisms
2013 - IRG/WP 13-20528
Molecular techniques are now routinely used in the identification, detection and analysis of wood degrading organisms. An overview of some of the early work on nucleic acid isolation and characterization will be followed by a discussion of the power of sequencing and other procedures for better understanding: the mechanisms involved in the biological degradation of wood, the metabolic basis of pre...
J Jellison, B Goodell, G Alfredsen, D Eastwood, G Daniel, S M Cragg, J K Grace
Method for determining the critical moisture level for mould growth on building materials
2013 - IRG/WP 13-20530
The natural conditions of relative humidity (RH) and temperature (T) in different parts of a building is rarely constant over time. Instead, RH and T often vary cyclically and may pose a risk of mould growth as these conditions are the two key environmental parameters that controls mould growth. Consideration to both humidity and temperature conditions and the susceptibility to mould in a material...
A Ekstrand-Tobin, P Johansson, G Bok
Development of a rapid method to assess the rate of fungal colonization of wood
2013 - IRG/WP 13-20531
Testing of wood durability is today done mainly with accelerated exposure tests under rather realistic conditions (in ground, outdoors with moisture traps etc). Although such tests are accelerated with respect to the conditions that outdoor exposed wood structures are exposed to, they tend to take rather long time. The present paper presents the development of a rapid method intended to assess at ...
L Wadsö
Surface energy characterization of thermally modified wood using inverse gas chromatography
2013 - IRG/WP 13-20532
The objective of this work is to characterize surface energetics of thermally modified wood. Such information may be useful for a better understanding and predictions of adhesion properties between the modified wood and other material systems, e.g. coatings, adhesives or matrices in composites. Inverse gas chromatography (IGC) was used to study the surface energy characteristics of thermally modif...
S Källbom, K Segerholm, D Jones, M Wålinder
Fungal laccases as a tool for wood functionalization
2013 - IRG/WP 13-20533
Wood degrading fungi are the most important production organisms for laccase, a promising oxidative biocatalyst with numerous biotechnological applications in the forest products industry. Laccases are multi-copper containing oxidases (EC 1.10.3.2), which catalyse mono-electronic oxidation of phenols, polyphenols and anilines at the expense of molecular oxygen. Interest in these essentially ‘eco...
M Schubert
Moisture distribution in glulam beams with natural cracks observed with CT Scanning before and after rain
2013 - IRG/WP 13-20534
The way cracks in outdoor wooden constructions affect durability is an interesting topic, since a certain amount of cracks can always be found naturally in wood and glued laminated wood. The question in this was, can cracks lead water into the wood and thereby increase the risk for decay and reduce strength and service life. Moisture balance, i.e., water absorption and water distribution were stud...
K Sandberg
Report on COST E37 Round Robin Tests – Comparison of results from laboratory and field tests
2013 - IRG/WP 13-20535
A round robin involving 15 European participants was set up in 2006. The round robin consists of both a field test according to the double layer test method and a laboratory test with two different preconditioning methods. When comparing EN 84 preconditioning (two weeks water leaching) with natural preconditioning (1 year in field, above ground) according to CEN/TS 15397, no significant difference...
M Westin, E Conti, J Creemers, P-O Flæte, A Gellerich, I Irbe, M Klamer, B Mazela, E Melcher, R Möller, L Nunes, S Palanti, L Reinprecht, E Suttie, H Viitanen