Your search resulted in 251 documents. Displaying 25 entries per page.
The effect on moisture content of water trapped in wood joints
2012 - IRG/WP 12-40613
To predict the service life of a structure, a model where the exposure of a structure is compared to its resistance can be used. Which exposure and resistance parameters that are relevant depend on which materials the structure consist of. This approach, with an exposure and a resistance parameter, is similar to the one used in structural engineering where a load (exposure) is compared to the bear...
M Fredriksson, L Wadsö, P Johansson
An assessment of soft rot in preservative-treated poles in two test sites and two network areas in New South Wales
2013 - IRG/WP 13-10801
This document presents an extended summary of recent investigations into soft rot attack of preservative treated power poles from the re-inspection of samples selected from two field sites and two in-service trials located in New South Wales, Australia. The in-ground sapwood of selected poles was assessed by probing and, after core sampling, by microscopy to determine the severity and extent of s...
W D Gardner, M A Powell, C Kirton
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
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
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
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
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
Modelling the risk for mould growth on timber stored outdoors protected from rain
2013 - IRG/WP 13-20529
A mould resistance design (MRD) model was used to calculate the maximum duration of storage of timber outdoors under cover (protected from rain) before the onset of mould growth on the surface of wood. The prediction model is based on laboratory tests performed in constant and cyclic climates and were also confirmed against exposure tests in attics and crawl spaces. The prediction model presented ...
E Frühwald Hansson, S Bardage, S Thelandersson
Estimation of service life of treated wood in ground contact based on early indicators
2013 - IRG/WP 13-20536
A well-known problem with field testing is that it takes a long time before meaningful and reliable results are achieved. Only when a trial has come to an end the so called average life for the samples in a group can be calculated and compared with other samples. The aim of the present study was to investigate if it is possible to get a reasonable and good estimation of the average life long befor...
M Hansson, J Jermer, P Larsson Brelid, N Terziev
Performance standards for wood in construction – delivering customer service life requirements
2013 - IRG/WP 13-20537
There is increasing need for consideration of performance classification for wood products in construction, as evidenced by the CPR, warranty providers and end user demands for information. This means we need to radically consider how the tests we conduct on wood for durability (especially biological durability) can inform on service life and how they might if possible be translated into a perform...
E Suttie, C Brischke, F Englund, E Heisel, J Jermer, D Lorenzo, M Polášek, S Thelandersson, J Van Acker
Performance of recent and old Sweet chestnut (Castanea sativa) wood
2014 - IRG/WP 14-10816
Sweet chestnut (Castanea sativa) hardwood is one of the most durable European wood species. In the present research, various aspects that could potentially influence the durability were elucidated, namely: presence of extractives, ring width, and weathering. Simultaneously, properties of wood, which was in outdoor use for 35 years, were elucidated as well. The results indicate that ring width and ...
M Humar, M Žlahtič, N Thaler
Performance classification of wood in construction – drafting a user friendly European standard
2014 - IRG/WP 14-20545
The performance classification for wood products in construction is an extremely important topic in Europe and beyond – warranty providers and end users demand service life and performance information in the face of competition with other materials. The European project PerformWOOD has formalised and drawn together the on-going research to focus on generation of a material resistance factor for ...
E Suttie, C Brischke, L Meyer, J Van Acker, M Kutnik, E Heisel, F Englund, J Jermer, S Thelandersson, M Polášek, D Lorenzo
Changes in mechanical and chemical properties of wood exposed outdoors
2014 - IRG/WP 14-20550
The aim of this study was to investigate differences in certain mechanical and chemical properties of three different wood species (common beach (Fagus sylvatica), Norway spruce (Picea abies), and copper-ethanolamine (CuE) impregnated Norway spruce (Picea abies)) that were exposed in use class 3 (CEN, 2006) for periods between 4 and 30 months. The results show, that changes in the investigated me...
N Thaler, C Brischke, D Žlindra, V Vek, M Humar
Critical parameters on moisture dynamics in relation to time of wetness as factor in service life prediction
2014 - IRG/WP 14-20555
The concept of natural durability or enhanced durability based on the presence of active ingredients having an impact on both fungi and insects is not the only parameter steering the material resistance. Complementary resistance to getting wet (wetting ability) and consequently the ease of drying afterwards will lead to a parameter related to the time a piece of wood will remain under such wet con...
J Van Acker, I De Windt, W Li, J Van den Bulcke
Cost effective extension of service life of bridge tie (sleepers) - Effectively applying borate during Boulton conditioning and treatment with copper naphthenate
2014 - IRG/WP 14-30637
Current longevity of creosote treated wooden bridge ties in the South Eastern US is about 15 to 25 years, which is well below of the average service life of 33-50 years of railroad ties. Such short service life increases costs associated with maintenance of railroads including bridge down time for tie replacement as well as the cost for the new ties themselves. Because of this, many railroads are...
J D Lloyd, T Chambers, J-W Kim
Acceptance levels of surface disfigurement - tolerance to defects of coated wood
2015 - IRG/WP 15-20564
Service life planning (PSL) has become an important issue in performance based building and substantial progress has been made in recent years. The role of predicting the aesthetical service life of wooden building components has been underestimated for quite long time but is recently attracting more and more notice. It is influenced by numerous factors such as discoloration, fading, flaking, crac...
C Brischke, P Kaudewitz
The combined effect of wetting ability and durability on field performance – verification of a new prediction approach
2015 - IRG/WP 15-20565
Comprehensive approaches to predict performance of wood products are requested by international standards and the first attempts have been made in the frame of European research projects. However, there is still an immanent need for a methodology to implement the durability and moisture performance of wood in a performance classification system. The aim of this study was therefore to establish an ...
C Brischke, G Alfredsen, P-O Flæte, M Humar, T Isaksson, L Meyer
Non-destructive monitoring of structure and moisture dynamics of plywood exposed outdoors to improve service life prediction and fit-for-purpose design
2015 - IRG/WP 15-20570
Plywood is an important construction material yet prone to water uptake, which can decrease strength and increase decay risk. To predict service life and improve fit-for-purpose design, it is crucial to understand the moisture behavior and structural changes of plywood. In this research, several plywood specimens were exposed outdoors for approximately one year. During this period, the moisture di...
W Li, J Van den Bulcke, I De Windt, M Dierick, J Van Acker
Performance of bio-based building materials – viewpoints from the first year of COST Action FP1303
2015 - IRG/WP 15-20572
Maintaining and expanding the market potential for bio-based building products in indoor and outdoor construction uses remains a key activity for industries in the forestry and biotechnological sector, particularly in Europe. Whilst there are ongoing activities within IRG for collecting and populating a database on performance on wood, the performance data for many other (i.e. non-wood) "environme...
D Jones
How to Increase the Lifespan of Exterior Wood Coatings
2015 - IRG/WP 15-40700
In addition to aesthetic appeal, coatings are designed to protect the wood from weathering degradation in outdoor conditions. This paper gives an overview of the effects of main components of coating, coating properties, and wood treatments on coating performance. Understanding how different type of resins (alkyd, acrylic or polyurethane), amount of pigments, type of solvents (organic or water), a...
M Nejad
Foundation piles: analysis of beech wood decay in service life conditions
2016 - IRG/WP 16-10858
Wood piles foundation system was largely used over decades. Thus, numerous buildings over the world are based on this constructive system. In the context of reduction of CO2 emissions in the building field of constructions, substitution of concrete by wood as material for foundation piles seems to be a promising alternative. However, fluctuation of the water table level in soil may promote fungal ...
Q Kleindienst, A Besserer, M-L Antoine, C Perrin, J-F Bocquet, L Bléron
Identification of the key factors influencing development of the blue stain fungi
2016 - IRG/WP 16-10872
Service life of wood is more and more frequently affected by aesthetic requirements than functional ones. In order to elucidate various aspects of service life, model house with façade elements made of 22 materials was built on the field test site at Department of Wood Science and Technology in Ljubljana. Colour and fungal disfigurement is among other parameters monitored on this house. In parall...
D Kržišnik, B Lesar, N Thaler, M Humar
Global survey on durability variation – on the effect of the reference species
2016 - IRG/WP 16-20573
Climate change due to anthropogenic emissions is the largest environmental challenge of our time. Forest-based value chains play an important role in reducing the accumulation of CO2 in the atmosphere. Maximizing the use of wood to tackle climate change requires improved understanding of the service life of timber products. This information can best be obtained from field testing and while there i...
R Stirling, G Alfredsen, C Brischke, I De Windt, L P Francis, E Frühwald Hansson, M Humar, J Jermer, M Klamer, M Kutnik, P Laks, I Le Bayon, S Metsä-Kortelainen, L Meyer-Veltrup, P I Morris, J Norton, T Singh, J Van Acker, J Van den Bulcke, T M Venås, H Viitanen, A H H Wong
CCA Treated Wood, Will It Last 100 Years?
2016 - IRG/WP 16-20575
Copper, chrome and arsenate (CCA) treated wood has a very successful history of use in New Zealand, for at least 60 years. In many parts of the world, CCA has been used for timber treatment since the mid-1930s. In this report, data are presented on the performance of CCA treated pine stakes and poles. Results from ground contact durability tests at Scion and other overseas test performance data su...
T Singh, D Page