Your search resulted in 586 documents. Displaying 25 entries per page.
Chapter 11 - Preservation of talla bamboo
2007 - IRG/WP 07-10635-11
Researches revealed that the talla bamboo (Bambusa tulda Roxb.))
in Bangladesh could be full-cell pressure treated with CCA in green
and dry conditions. The dry bamboo gives higher loading
absorptions than green one when impregnated at same treating
conditions. Also higher absorptions are obtained at nodes rather
than internodes. Adequate penetration and retention results for
ground and wate...
A K Lahiry
Quantitative design guideline for wood outdoors above ground applications
2011 - IRG/WP 11-20465
This paper describes the background and principles behind an engineering design guideline for wood in outdoor above ground applications, i.e. use class 3 according to EN 335. The guideline has been developed in the European research project WoodExter and can be seen as a first prototype for a quantitative design tool in the area of wood durability. It is based on a defined limit state for onset of...
S Thelandersson, T Isaksson, E Suttie, E Frühwald, T Toratti, G Grüll, H Viitanen, J Jermer
Methods of field data evaluation - time versus reliability
2011 - IRG/WP 11-20466
Field testing of wood and wood-based products is so far the most reliable way to get information on performance with respect to durability and expected service life. However, field trials are extremely time and cost consuming. The main objective of the present study was to investigate possible correlations between early stages of decay, preferably during the first 5 years, and the actual service l...
P Larsson Brelid, C Brischke, A O Rapp, M Hansson, M Westin, J Jermer, A Pilgård
Aesthetic service life of coated and uncoated wooden cladding - influencing factors and modelling
2011 - IRG/WP 11-20470
Mould growth on exterior coated cladding façades is an undesirable element and will often shorten the aesthetical service life. Mould growth on painted surfaces is influenced by type and concentration of film fungicides, the paint formulation and the wood substrate itself, and wooden cladding may experience exponential fungal deterioration caused by variation in the climatic factors, often within...
L Ross Gobakken, O A Høibø
Performances of Douglas fir in real outdoor use conditions
2011 - IRG/WP 11-20472
The European standard EN 350-2 classifies Douglas fir as moderately resistant to fungal decay on the basis of standardized laboratory and field tests. However, the lifespan expectancy of outdoor structures such as cladding, decking and elements of wood construction carpentry may also vary according to environmental conditions (climate, exposure to weathering), maintenance and design. An investigat...
M Kutnik, S Lepetit, S Le Nevé
In-ground variability of decay intensity within a test field
2012 - IRG/WP 12-20496
Timber exposed in the ground faces most severe conditions in terms of exposure to wetting and fungal decay in the terrestrial environment, therefore wood durability tests are often conducted in test fields preferably ensuring the occurrence of all relevant decay organisms. One can also expect differences in decay within an individual field-test site due to localized distribution of certain organis...
C Brischke, S Olberding, L Meyer, T Bornemann, C R Welzbacher
Durability of timber products – Part 2: Proposal for an IRGWP - Durability Database
2012 - IRG/WP 12-20497
A proposal for a web-based platform for scientific exchange of test data in the field of wood durability and wood protection has been made. The overall aim of the durability data base is to improve the usability of existing test data and to create an added value for durability research and service life prediction.
The database allows for test results from standardized and non-standardized laborat...
C Brischke, L Meyer, G Alfredsen, M Humar, L Francis
Durability of timber products –Part 1: Inventory and evaluation of above ground data
2012 - IRG/WP12-20498
The material-inherent resistance of wood is one of the most important qualities influencing the durability of timber. Hence, it has also a major effect on the service life to be expected from a timber construction. In addition, design details and the respective climatic conditions determine durability and make it impossible to treat wood durability as an absolute value. Moreover, the reference mag...
C Brischke, L Meyer, G Alfredsen, M Humar, L Francis, P O Flæte, P Larsson Brelid
Effectiveness of CCA-C and CCB preservatives after a 30 years stake test
2012 - IRG/WP 12-30606
The objective of this experiment was to assess the durability of four pine species treated with waterborne preservatives. In order to determinate this, a stake field test, following the IUFRO (International Union of Forestry Research Organizations) recommendations, was installed at Experimental Station of Luiz Antonio (21º 32’ S and 47º 42’ W), State of São Paulo, Brazil.
Species under t...
I PJankowsky, E S Lepage, C Salvela, J M Vidal, S Takeshita
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
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
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
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
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
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