Your search resulted in 6688 documents. Displaying 25 entries per page.
Case study: “Riesenbühlturm”
2017 - IRG/WP 17-20599
In this case study four 7 m long Douglas fir crossbeams were investigated regarding the remaining metal and moisture content. The crossbeams were replaced from a timber tower after 10 years of service in the Black Forest region (South Germany) due to fungal decay. From each of the crossbeams five stem discs were taken and relevant parameters (density, moisture and remaining metal content) were de...
E Melcher, J Müller
Comparison of 1H qNMR and NIR spectroscopic methods to predict heartwood decay resistance in Dicorynia guianensis Amsh
2017 - IRG/WP 17-20601
Dicorynia guianensis is by far the most exploited wood in French Guiana, as it is an abundant tree species associated with good technological properties. However, the decay resistance of D. guianensis wood against lignivorous fungi pathogens is sometimes variable. Therefore, the development of tools to predict the decay resistance of D. guianensis heartwood is relevant in wood science and agrofore...
C Flora, G Frédéric, M-F Thevenon, Y Estevez, C Duplais, N Amusant
Use of small volume cups in XRF analysis of treated wood retention
2017 - IRG/WP 17-20602
Efforts are underway in the United States to improve the conformance of commercially-treated wood with the applicable retention standards. As part of an effort to devise a practical method for on-site assessment of within-charge retention variation, we investigated whether small-volume x-ray florescence (XRF) sample cups could be used with treated wood. A range of cup sizes, preservative types, re...
R Stelzer, A Taylor, P Lebow
Design and performance prediction of timber structures based on a factorization approach
2017 - IRG/WP 17-20603
Service life of timber structures in outdoor conditions is predominantly affected by the climatic conditions in terms of moisture and temperature over time. On the one hand, the two parameters moisture content and temperature determine the exposure-induced dosage that can lead to fungal infestation and subsequent decay. On the other hand, the material resistance of wood stands in opposition to exp...
L Meyer-Veltrup, C Brischke
Laboratory test to determine the effect on durability of combining biobased building materials with timber in construction
2017 - IRG/WP 17-20604
The use of Structural Insulated panels is a construction approach that is seeing more abundant use and is becoming a widely available method. Preformed units are usually a composite structure which often include a range of bio-based materials such as timber, wool or straw. Traditional laboratory based wood decay tests do not take into account this combination of biobased materials and it may be po...
S F Curling, G A Ormondroyd
The sorption behaviour of wood
2017 - IRG/WP 17-20605
The use of dynamic vapour sorption to determine the sorption properties of wood has become an increasingly popular technique. The method has many advantages when compared with many other gravimetric methods. However, it is necessary to set an equilibrium condition in order to obtain data for an isotherm in a reasonable amount of time. An important recent finding has been that multiple sorption cyc...
C Hill
Quality of the impregnated wood in the Slovenian hardware stores
2017 - IRG/WP 17-20606
Ten different samples from Slovenian hardware stores were analysed. Samples were treated with copper based wood preservatives and designed and advertised to be used in heavy duty applications in use classes 3.2 or 4. In order to determine the quality of the treatment penetration, retention and fungicidal properties were determined. Retention was determined with XRF analysis, while modified EN 113 ...
M Humar, B Lesar, N Thaler, D Kržišnik, N Kregar, S Drnovšek
Monitoring of wood biodeterioration by infrared spectroscopy
2017 - IRG/WP 17-20607
The susceptibility of wood to deterioration by rotting fungi is intrinsically related to its chemical composition and the environmental conditions at its place of use, and if not detected in time, can cause enormous financial losses. The process of wood biodeterioration by decay fungi can be evaluated through laboratory accelerated test, in specific field tests, or through non-destructive techniqu...
E Meneses Oliveira, A Florian da Costa, J W Batista Braga
Consistency of performance of acetylated wood
2017 - IRG/WP 17-20608
It is well known that acetylation of wood improves the resistance against wood decaying fungi and insects, as well as its dimensional stability under varying moisture conditions. Accsys Group continues to support a variety of laboratory and field studies around the world to assess and monitor the durability, dimensional stability and uniformity of its products. To gain and maintain market acceptan...
F Bongers, J van Zetten
Bio-deterioration of Southern Pine Stakes at Geographically Different Testing Sites
2017 - IRG/WP 17-20609
Southern pine (SP) sapwood is commonly used in preparing the standardized stakes for performance testing as referenced in the American Wood Protection Association (AWPA) Book of Standards. For example, the standardized above ground test methods E16/E18 and the standardized ground contact test method E7 all use sapwood of SP as the preferred wood species for preservative performance test. In this...
Jun Zhang, J Horton
Redwood Durability in NZ – Can pure culture laboratory tests predict outdoor service life
2017 - IRG/WP 17-20610
Coast Redwood (Sequoia sempervirens) is an alternative species in New Zealand to the large scale Pinus radiata plantations. Redwood is classified as moderately durable but its durability is extremely variable. In order to reduce this variability in future stock, understanding growth conditions, clone, and tree age effects are important however this involves many samples and is not suitable for ass...
D O’Callahan, C Chittenden, J van der Waals, D Meason, T Singh
Three-Dimensional Digital Image Correlation of Strains in Profiled Wood Decking Exposed to Wetting & Drying
2017 - IRG/WP 17-20611
We use three dimensional digital image correlation to measure the strains that develop at the surface of profiled radiata pine (Pinus radiata D. Don) deck boards subjected to a wetting and drying cycle. We hypothesise that surface profiling will change the pattern of strain distribution at the surface of deck boards by concentrating stresses at the base of profile grooves. Five groups of three deck board samples were produced from five different pieces of machine stress-graded radiata pine wood. Two wavy profiles, ribble or ripple, were tested. Flat unprofiled boards acted a control. Each board was fixed to a rigid frame and subjected to a wetting and drying cycle. Full field surface strain data was collected using 3D digital image correlation. Strains varied across the surface of both flat and profiled boards. Profiling changed surface strain patterns; strain maxima and minima developed in the profile ridges and grooves during wetting, respectively, but this pattern of strains reversed during drying. Such a pronounced reversal of strains was not observed when flat boards were exposed to wetting and drying, although there was a shift towards negative strains when flat boards were dried. We conclude that profiling changes surface strain distribution in deck boards exposed to wetting and drying, and causes high strains to develop in the grooves of profiled boards. These findings help explain why checks in profiled deck boards are mainly confined to profile grooves where they are difficult to see, and the success of profiling at reducing the negative effects of checking on the appearance of wood decking.
J Mallet, S Kalyanasundaram, P D Evansa
Rapid detection of the Alaska yellow cedar, Callitropsis nootkatensis (Cupressaceae) extractives using Fourier transform infrared (FT-IR) spectroscopy
2017 - IRG/WP 17-20612
Global changes in wood harvesting towards plantation species grown on much shorter rotations has the potential to markedly alter wood quality perceptions. Nowhere is this more risky than with naturally durable species where there is compelling evidence that faster grown woods tend to be less durable. The ability to non-destructively assess durability may allow growers to identify materials that re...
S Lipeh, J J Morrell
Modelling of moisture content in timber bridge details
2017 - IRG/WP 17-20613
The design of details is an important aspect in durability design of timber bridges. Details are often considered the weakest points in bridges due to their tendency to trap and accumulate moisture and thus facilitate decay. When designing maintenance plans and inspection intervals, it is important to know how design choices will come to influence the service life. Moreover, service life and wood ...
J Niklewski, C Brischke, E Frühwald Hansson, L Meyer-Veltrup
Monitoring Diversity and Colonization Patterns of Wood-Inhabiting Fungi Using Field Stake Tests
2017 - IRG/WP 17-20614
Advances in molecular identification of microbial communities enabling rapid microorganism determination have allowed ecological data to be increasingly incorporated into standardized wood performance tests. Combining standard field tests with molecular methods to study wood-associated microflora can help to better understand fungal colonization and decay processes of wood in service. The potentia...
P Torres-Andrade, J Cappellazzi, J J Morrell
Comparative Durability of Timber Bridges in the USA
2017 - IRG/WP 17-20615
As engineers begin to utilize life-cycle-cost design approaches for timber bridges, there is a necessity for more reliable data about their durability and expected service life. This paper summarizes a comprehensive effort to assess the current condition of more than one hundred timber highway bridge superstructures throughout the United States. This national study was jointly administered by the ...
J P Wacker, B K Brashaw
Overview of the treated wood quality control program in the United States with the recent challenges and advances
2017 - IRG/WP 17-20616
In the past two decades, there have been significant and rapid changes in wood protection technologies for residential applications which have moved away from long established heavy duty metal oxide based products such as chromated copper arsenate (CCA). The successor generation of wood protection systems usually contain copper as the primary biocide, in combination with carbon-based co-biocides s...
L Jin
Evaluation of surface cracks on wood – physical assessment versus subjective sensation
2017 - IRG/WP 17-20617
In the presented studies from the University of Goettingen (Study I) and the University of Hannover (Study II), the assessment of cracks with different methods and their acceptance in general as well as depending on different target groups are investigated. The aim was to determine which factors are relevant for a crack evaluation and which visual impression of a wooden surface is tolerable for co...
A Gellerich, C Brischke, L Emmerich, L Meyer-Veltrup, P Kaudewitz
Prediction of service life – does aesthetic matter?
2017 - IRG/WP 17-20618
Building structures should be designed in order to satisfy requirements regarding safety, serviceability, durability and aesthetics, assuring proper structure performance along the entire service life. For that reason it is essential to understand overall deterioration mechanism at levels of element, component, façade and entire building. This work focuses specifically on the façade aesthetical ...
A Sandak, J Sandak
Influence of Weathering on Moisture Performance of Wood
2017 - IRG/WP 17-20619
Water performance of wood is besides the inherent durability the most important factor that influences on the performance of wood in outdoor, above ground applications. Therefore it is of significant importance to optimize the methods that are able to predict the moisture behaviour of wood in outdoor applications. In order to elucidate this questions, samples were prepared of oak (Quercus), sweet ...
M Žlahtič-Zupanc, B Lesar, N Thaler, M Humar
COST FP 1303 Cooperative Performance Test – Results after two years outdoor exposure
2017 - IRG/WP 17-20620
COST Action FP 1303 ‘Performance of Bio-Based Building Materials’ started in October 2013 and an ambitious program was set up for four years. Among this a collaborative field test was planned. The idea of the cooperative performance test was to distribute a fairly simple test set up to as many places in Europe as possible in order to collect performance data reflecting the full range of climat...
B Lesar, M Humar, C Brischke, L Meyer-Veltrup, D Jones, N Thaler, J M Abascal, G Alfredsen, B Brunnhuber, E Grodås, M Irle, J Kers, M Klamer, K-C Mahnert, E Melcher, S Palanti, M Noël, E Suttie, N Pfabigan, M Touza
Moisture performance of wood determined in laboratory and field trials
2017 - IRG/WP 17-20621
It is widely accepted that wood moisture content (MC) is the key factor when it comes to durability of wooden structures exposed to weathering. The moisture performance of wood and wood-based products has been recognized as key element in wood durability and wood protection. Actually, it should be considered as major component of the material-intrinsic resistance of wood, but never found its way i...
D Kržišnik, N Thaler, B Lesar, M Humar
Moisture content as a quality control parameter in thermally modified timber production
2017 - IRG/WP 17-20622
Quality assurance (QA) or factory production control (FPC) is necessary to ensure a proper production process. The requirements of QA/FPC can result from EN and national standards, quality assurance systems, or producer-specific rules.
TMT producers must ensure that the process was correct, and to ensure traceability of products. In addition to the electronic records, the material should be che...
W Scheiding, H Turkulin, S Stein
An experimental study of mould growth and wood decay in timber frame walls
2017 - IRG/WP 17-20623
This paper deals with parameters related to the occurrence of mould growth and wood decay in timber frame walls. In a first part, the hygrothermal conditions inside a timber frame wall finished with brick veneer cladding are analysed to get an idea of possible moisture related problems. It is shown that, based on the VTT mould prediction model, there is a mould risk on the interface between the in...
M Vanpachtenbeke, J Van den Bulcke, I De Windt, J Langmans, S Roels, J Van Acker
New Standards for Approval of Modified Wood within the Nordic Wood Preservation Council (NWPC)
2017 - IRG/WP 17-20624
In the Nordic countries, there is a long tradition for quality labelling of preservative treated wood. Until now the labelling has been restricted to pine and other easy to treat wood species, but with the introduction of a new set of standards it is now possible to obtain the Nordic Wood Preservation Council’s (NWPC) quality labelling also for modified wood.
In this paper, we will introduce th...
N Morsing, E Engelund Thybring, M Klamer