Your search resulted in 76 documents. Displaying 25 entries per page.
Moisture adsorption isotherms of wood studies using a dynamic vapour sorption apparatus
2009 - IRG/WP 09-20398
Five types of wood including two Malaysian hardwoods acacia mangium (Acacia mangium) and sesenduk (Endospermum malaccense), two temperate softwoods, Sitka spruce (Picea sitchensis), radiata pine (Pinus radiata) and Accoya (commercially modified wood) were studied to determine their moisture sorption behaviour using a Dynamic Vapour Sorption (DVS) apparatus. The isotherm plot for each species teste...
J Zaihan, C A S Hill, S Curling
Estimating the age of subterranean termite attack and damage in buildings
2010 - IRG/WP 10-10727
This paper describes physical and experimental methods and a mathematical model (Rotramel 2003) to assist in estimating the age of subterranean termite attack and damage to building structures. Timber, building and termite management industries have to develop new strategies to assess and estimate termite attack and damage in the current climate of global warming. A case study will be used as an e...
J R J French, B M Ahmed Shiday, J Thorpe
Simulation and Investigation of Wood Degradation by Erosion Bacteria in Laboratory Experiments
2010 - IRG/WP 10-20431
A Microcosm experiment was successfully set up to establish, monitor and manipulate bacterial wood degradation under low oxygen conditions. Sound pine sticks were placed in waterlogged sediment from a heavily decayed pine pile foundation site in Amsterdam. The system was subject to different gassing treatment regimes in order to investigate the role of oxygen in the bacterial degradation process o...
J Gelbrich, E I Kretschmar, N Lamersdorf, 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
Assessment of Boracol 200RH (FrameSaver) as a remedial treatment to control decay in pre-decayed model timber frame units
2010 - IRG/WP 10-30529
Model timber frame units constructed from untreated radiata pine were pre-wetted to approximately 40% moisture content and inoculated with Coniophora puteana and Oligoporus placenta. Units were transferred to a controlled environment room maintained at 25°C and 95% RH for 7 and 10 weeks to allow two levels of decay to become established in units. Following pre-decay, units were disassembled, clea...
Mick Hedley, Dave Page, Jackie van der Waals
Kinetic Water Vapour Sorption of Sitka Spruce at Variable Temperature Using the Parallel Exponential Kinetics Model
2010 - IRG/WP 10-40512
In this study the water vapour sorption of Sitka spruce (Picea sitchensis (Bongard) Carr.) was measured using a Dynamic Vapour Sorption (DVS) apparatus and then analysed using the parallel exponential kinetics (PEK) model. The water vapour sorption rate of wood quickly increased when the relative humidity was changed. With the elapse of time, the sorption rate gradually decreased within any specif...
Yanjun Xie, C Hill
A survey of factors affecting decay resistance of wood modified with acetic anhydride
2012 - IRG/WP 12-40594
From the range of information published, acetylation appears well suited to provide adequate protection against biological attack for materials derived from typically non-durable wood species. Acetylated wood is now commercially available both in Europe and in the USA. But still there are a lot of unanswered questions related to fungal decay mechanisms in acetylated wood. The paper summarize exist...
G Alfredsen, P O Flæte, H Militz
Application of a model for the prediction of fungal degradation of thermally modified beech timber by Trametes versicolor
2013 - IRG/WP 13-40622
Colour measurement technology is found to be feasible for characterization of the property changes of thermally modified timber (TMT). In opposite to time-consuming and expensive laboratory tests a non-destructive test represents an improvement for the manufacturer of TMT. Therefore the aim of this study was to develop a method which allows sorting the different treatment intensities after the man...
Clauder, L., Richter S., Unger, W., Pfriem, A
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
Interaction between Aspergillus niger fungus and other filamentous fungi on salt-agar medium and their growth on natural wood and wood treated with fungicide
2015 - IRG/WP 15-20569
Aspergillus niger (An) is very often used alone or in mixture with other filamentous fungi of the genus in testing biocides in disinfection procedures, safety, hygiene, medical fields as well as for testing resistance of wood and wood-based materials to moulds. Softwood species as well as hardwood are overgrown with An fungus very easily, causing drop of mainly the aesthetic value of wood product....
A Fojutowski, A Kropacz, A Koziróg
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
Simulation of surface climate and mould growth on wooden façades
2016 - IRG/WP 16-20585
The weathering of wooden surfaces is normally caused by mould growth, lignin deterioration and leaching of extractives. For well insulated buildings, the effect of the interior climate on the outer surface is small and sometimes negligible. This paper describes simple models for surface temperature and moisture conditions on a wooden façade that can further be used to model weather degradation an...
T K Thiis, I Burud, D Kraniotis, L Ross Gobakken
Development of decay hazard maps based on decay prediction models
2016 - IRG/WP 16-20588
Durability plays a very central role in timber engineering, especially when working with wood in use class 3 and above where the risk of decay is high. As one of the primary decay influencing factors, the external condition, i.e. the local climate, is often graded by some type of climate index value. Predominately, climate indices are based on a direct relationship between weather data and decay. ...
J Niklewski, E Frühwald Hansson, C Brischke, D Kavurmaci
Hygrothermal performance of ventilated wooden cladding
2016 - IRG/WP 16-40733
The risk for an attack of wooden claddings by decay and discolouring fungi strongly depends on the moisture and temperature conditions in the building envelope. The design of the cladding has a major influence on its hygrothermal performance. In the present study, different wooden ventilated cladding designs were investigated at a test house in Mid-Norway for four years. The objective was to incre...
K Nore, U Hundhausen
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
Natural durability, ethanol-toluene extractives and phenol content prediction of eight wood species from Madagascar using NIRS multispecific models
2018 - IRG/WP 18-10926
Madagascar has nearly 4000 species of trees and shrubs, but wood properties of only 200 species have been studied. Some properties, such as the natural durability or chemical composition are of importance for adequate and optimal use of these timber species. Since durability tests take long time and chemical analyzes can be very expensive, alternative methods such as near infrared spectroscopy (NI...
A R Razafimahatratra, H Rakotovololonalimanana, M-F Thévenon, C Belloncle, G Chaix, T Ramananantoandro
Simulation and visualization of aesthetic performance of bio-based building skin
2018 - IRG/WP 18-20633
Performance of 120 selected façade materials provided by over 30 industrial and academic partners is under evaluation. The experimental data, acquired during BIO4ever project duration are used for development of the numerical models simulating the material degradation in a function of time and exposure. The weather data calculated according to the ASHRAE 2013 database allows numerical simulation ...
J Sandak, A Sandak, P Grossi, M Petrillo
Non-stochiometric oxidation and ROS generation promoted by guaiacol lignin structures and lignocelluose surfaces may be a component of brown rot fungal degradation mechanisms
2019 - IRG/WP 19-10937
Model guaiacol compounds representing lignin monomers, as well as DHP-lignin and wood flour of controlled particle size were used to assess iron reduction at the pH of the natural wood cell wall. All compounds functioned as electron donors for ferric iron, with the lignin monomers demonstrating capacity for non-stochiometric reduction of iron with multiple moles of ferric ion reduced per mole of l...
Y Tamarua, M Yoshidaa, L D Eltisb, B Goodell
Comparative performance of wood/wood-based claddings predicted by four hygrothermal simulation tools
2019 - IRG/WP 19-20646
A number of hygrothermal numerical simulation packages are available, either wholly or partially dedicated to heat, air and moisture transfer simulations of building materials and wall assemblies. The objective of this work was to compare the hygrothermal responses and the moisture performance of western red cedar and composite wood claddings of a wood frame wall as predicted by four hygrothermal ...
M Defo, M Lacasse, A Laouadi
Performance of wood decking after 5 years of exposure: verification of the combined effect of wetting ability and durability
2019 - IRG/WP 19-20647
Wood is one of the most important construction materials and its use in building applications has further expanded in recent decades. In order to enable even more extensive and reliable use of wood, factors affecting wood’s service life need to be understood. More recently, a new concept to characterize the durability of wood-based materials and to predict the service lives of wood was proposed,...
M Humar, D Krzisnik, B Lesar, C Brischke
Using satellite-retrieved soil moisture data to model the decay risk of in-ground timber
2022 - IRG/WP 22-20689
Satellite-derived soil moisture data from the Soil Moisture Active Passive (SMAP) was extracted for a 9 x 9 km point grid over Europe. The data was then used as input to a dose-response wood decay model based on terrestrial microcosm (TMC) tests. The resulting hazard map plotted dose as an indicator of in-ground wood decay based on differences in annual temperature and soil moisture characteristic...
P B van Niekerk, M Schönauer, B N Marais, C Brischke
Molecular dynamics investigation of wood modification with furfuryl alcohol
2022 - IRG/WP 22-40931
Molecular dynamics (MD) was applied to investigate and understand the structural characteristics and the interaction of cellulose and lignin with furfuryl alcohol for explaining the wood modification process. A single chain of cellulose polymer model and a softwood lignin model was considered to represent cellulose and lignin polymers. The obtained radial distribution function results revealed tha...
V Ponnuchamy, J Sandak, A Sandak
Investigating moisture dynamics and fungal decay risk: integrating X-ray CT visualization and simulation benchmarks through a Fungal Control Unit
2024 - IRG/WP 24-11045
Wood is susceptible to fungal attack and over time the structural integrity can be compromised. This risk is of course strongly related to moisture dynamics, as moisture is needed for fungal growth. While existing methodologies, such as lab and field tests, provide valuable insights into wood decay, they often fall short in replicating real-life conditions, particularly within the intricacies of t...
J Van den Bulcke, J Van Acker, M Delbeke, A Blommaert, N Van Den Bossche, M Steeman, L De Ligne
Phytosanitary heat treatment of wood in a laboratory drying oven and, in a pilot-scale kiln using the house longhorn beetle (Hylotrupes bajulus) larvae as a model
2024 - IRG/WP 24-20722
International trade in wood products brings the risk of the movement of tree pests which can cause devasting ecosystem and economic damage. International phytosanitary guidelines were created to help countries that import wood products. Import requirements intend to minimize pest spreading. Thus, the ISPM 15 (International Standards for Phytosanitary Measures No. 15) which specifies the “Regulat...
B Rubio, C L’Hostis, M Montibus, I Paulmier, C Brunet, L Charron, J-P Gaussorgues, C Guiberteau, V Vlahakis, F-R de Cibon, I Le Bayon
Changes in decay risk of wood in ground contact over Europe, from analysis of historic climate conditions
2024 - IRG/WP 24-41008
Changing climate conditions will affect global temperature and precipitation patterns, shifting some geographical areas into states that are more suitable for fungal wood decay. Climate normals, which are taken over a 30-year period, capture vast spatial and temporal variations in these conditions and comparing these can show changes over time. Importantly, being able to identify locations that ha...
P B van Niekerk, B N Marais, G Alfredsen, C Brischke