Your search resulted in 3288 documents. Displaying 25 entries per page.
Using X-ray scattering to elucidate the mechanisms behind the moisture and fungal decay resistance of epoxybutene modified wood
2019 - IRG/WP 19-40854
Chemical modification of the hydroxyl groups of wood can improve the properties of wood by providing moisture and biological resistance, as well as dimensional stability. Southern pine solid wood was chemically modified to various weight percentage gains (WPG) with epoxybutene (EpB, 8%-38% WPG). After modification, specimens were extracted with a toluene: ethanol (2:1) solution for 2 hours or wate...
R E Ibach, N Plaza
The impact of additional interior layers to the moisture dry-out and mould growth risk of CLT walls
2019 - IRG/WP 19-40876
The objective of this study was intended to determine the maximum allowable initial moisture content for CLT walls having both exterior and interior thermal insulation. A laboratory test was conducted, for which four test walls with two different insulation solutions and two different initial moisture contents were built. Based on the test results a simulation model was configured and simulations ...
V Kukk, J Kers, T Kalamees
Durability and climate change - implications for wood building structures
2019 - IRG/WP 19-50361
Sustainable building practices are rooted in the need for reliable information on the long-term performance of building materials; specifically, the expected service-life of building materials, components, and assemblies. This need is ever more evident given the anticipated effects of climate change on the built environment and the many governmental initiatives world-wide focused on ensuring that ...
M Lacasse
Studying amount, location and state of water in modified wood at moisture levels relevant for fungal degradation
2020 - IRG/WP 20-40889
Water is an essential parameter for fungal degradation of wood, but degradation primarily occurs at high moisture levels at water potential in the range of -4 to -0.1 MPa, which corresponds to 97-99.9% relative humidity. At these moisture levels, water is present in the wood structure both in and outside of cell walls. The majority of previous studies on the interaction between wood and water for ...
M Fredriksson, E Engelund Thybring, Ramunas Digaitis
Long-term field exposure of wood-plastic composites processed on a commercial-size extruder
2020 - IRG/WP 20-40894
Wood-plastic composites (WPC) contain wood fiber (or flour), thermoplastics and additives and are exposed to UV light, moisture, and biological deterioration in outdoor installations. Accelerated laboratory tests can help to predict the durability of WPCs, but long term evaluations are needed to validate these results. Field exposed above-ground WPC deck boards (30.5 x 139.7 x 609.6 mm) and in-gro...
R E Ibach, C M Clemmons, N M Stark
Impregnation of railway sleepers - Investigation of a system-sleeper as an alternative for creosote treated sleepers
2020 - IRG/WP 20-40896
For nearly 200 years wooden railway sleepers are impregnated with creosote. After initially using vacuum pressure processes for impregnation, empty-cell processes have been developed quickly and are used until today. Because of political developments, creosote will probably be banned on the European market in the near future. The Fürstenberg-System-Sleeper, which combines for Europe innovative as...
M Starck, A Heidel, C Brischke, H Militz
Studies on the material resistance and moisture dynamics of Douglas fir and Sitka spruce from Slovenia
2021 - IRG/WP 21-20677
Wood in outdoor applications is subject to various decomposition factors. Wood degradation can be prevented by construction details, biocide protection of wood, wood modification, or selection of naturally durable wood species. Unfortunately, the majority of timber species in Europe do not have naturally durable wood. Imported tree species represent a new pool from which we can draw wood species w...
M Humar, B Lesar, D Krzisnik, E Kerzic, R Brus
Effect of a Water Repellent Treatment on Moisture Behavior of Three Australian Hardwoods: A Preliminary Report
2021 - IRG/WP 21-40921
Wood is inherently hygroscopic and will sorb moisture either directly from the atmosphere or via capillary action. Moisture can have marked effects on wood properties and repeated wetting and drying creates dimensional changes that lead to physical damage. Exposure to elevated moisture levels also increases the risk of fungal attack.
Wood preservatives have long been used to minimize the risk of ...
B Hassan, J J Morrell, K Wood
Natural durability and moisture dynamics of commercially important European wood species after weathering
2022 - IRG/WP 22-10992
Wood is a frequently used material. Timbers’ mechanical properties, particularly its favourable strength-to-mass ratio, make them suitable for many uses. Current environmental awareness has led to its renewed importance as a building material. However, wood is susceptible to decay that severely affect its outdoor performance. This study investigated how weathering affects the natural durability ...
E Keržič, M Humar
Significance of the thermal design and the sorption isotherm shape in hygroscopic wood moisture dynamics and service life
2022 - IRG/WP 22-20682
Moisture dynamics are considered important for predicting the service performance of wood in exterior applications. Above a critical moisture content, water acts a softener on the structural polymer matrix of the wood cell wall, enabling the necessary diffusion of molecular species involved in the fungal degradation mechanism of wood. Water may enter solid wood in either liquid form or in vapor fo...
W Willems
Steam Pre-conditioning Treatment Prior to Acetylation: Impact on Dimensional Stability, Moisture Response Behaviour, and White-Rot Fungal Resistance of Hevea brasiliensis and Mitragyna ciliata Wood
2022 - IRG/WP 22-40930
The effect of steam pre-conditioning treatment on the dimensional stability, moisture response behaviour, and durability against white-rot fungus P. chrysosporium of acetylated Hevea brasiliensis and Mitragyna ciliata wood species were assessed. Defect-free specimens of both species from the top, middle, and base positions were selected, prepared according to ASTM D143-09 & ASTM D-2017 standards a...
E Uchechukwu Opara, J Mayowa Owoyemi, J Adeola Fuwape
Premature adhesion failure of exterior wood coatings – The influence of substrate temperature at coating application and moisture accumulation during storage
2022 - IRG/WP 22-40937
The present study aimed at extending the knowledge about premature coating failures of industrially finished wood cladding. Two potential factors were studied: the influence of substrate temperature at coating application and moisture accumulation during storage on the adhesion of waterborne coating systems. In the first experiment, 4 batches of wood specimens were submitted to 4 different tempera...
U Hundhausen
Effect of densification of Eucalyptus nitens and E. obliqua on moisture uptake, swelling, decay resistance, and fire performance
2022 - IRG/WP 22-40946
Some Australian Eucalyptus species that are abundantly available have low natural durability and poor resistance to fire. These same species are also extremely difficult to treat with preservatives or fire retardants using conventional pressure treatment methods due to a large proportion of refractory heartwood. The aim of this research was to understand whether thermo-mechanical densification had...
B Hassan, J J Morrell, F Wiesner, W Wu, B Belleville, K C Wood
Effect of Moisture Cycles and Timber Treatment on the Performance of Screwed Connections
2023 - IRG/WP 23-20694
The impact of moisture in timber structures is associated with the deterioration of timber, and loss of mechanical performance. Methods have been developed to treat timber using chemicals to inhibit deterioration, however, water intrusion has much more immediate effects on the mechanical properties of timber associated with swelling and shrinkage of the wood. The effects of moisture on the mechani...
L Yermán, M Xiao, Z Yan, L-M Ottenhaus
Biological durability and wood-water interactions of sorbitol and citric acid modified wood – Effects on the expected service life
2023 - IRG/WP 23-40960
A high level of research activities on sorbitol and citric acid (SorCA) modified wood has been recognized in Europe over the last few years. As this treatment is close to entering an industrial-scale production, it is of interest to investigate how such treated wood performs upon long-term outdoor exposure. Hence, in this study Scots pine (Pinus sylvestris L.) sapwood was modified with aqueous sol...
K Kurkowiak, L Emmerich, H Militz
Failure characteristics of thermally modified poplar wood subjected to mechanical tests
2023 - IRG/WP 23-40983
Poplar (Populus spp.) are among the fastest growing timber species and have been widely planted for use in plywood, composites, pallets, furniture components and paper production. However, the low density of the wood limits many structural applications and the wood has little resistance to biodegradation. Thermal modification represents one approach to improving durability by changing the moistur...
E Bari, M Ghorbanian Far, N Moradi, J J Morrell, G Daniel, B Mohebby, R Hosseinpourpia, M Humar
Intra-species variability of moisture dynamics in wood
2024 - IRG/WP 24-11040
Moisture dynamics of wood and wood-based materials play a major role in wood durability against different decay organisms. Their impact becomes particularly evident when wood is exposed, but not permanently wet. To date, however, this has only been taken into account indirectly and therefore inadequately when testing the durability of wood. While test methods are available, for example to determin...
C Brischke, H Purps, L Emmerich
Wood above ground project – Results and future plans
2024 - IRG/WP 24-11041
In 2000, the Danish Technological Institute (DTI) initiated an extensive study to investigate the natural durability of wood. The study involved exposing wood in various orientations to assess its performance. A total of 35 wood material types were exposed at DTI test site in Taastrup, Denmark. Moisture content (MC) was measured through weighing for the initial five years, decay was assessed follo...
A W Christof, R Digaitis, P Fynholm, J Stenbaek, N Morsing, B Lindegaard
International joint field trial on the moisture performance of wood – Set up and first results
2024 - IRG/WP 24-40996
Wood durability to decay stems from its inherent resistance to fungi resistance to fungi. In this regard, wood's ability to withstand moisture uptake plays an important role as the lower threshold for wood decay is a moisture content of 25%. However, the aspect of moisture resistance is not yet sufficiently emphasized as a durability factor, both in the assessment of durability as a material prope...
C Brischke, et al. (33 co-authors)
Modelling the service life of wood in ground contact – Verification of remotely sensed soil data from the reanalysis dataset ERA5-Land using in-situ measurements at a test site of utility poles in Eastern Norway
2024 - IRG/WP 24-41003
This study compared soil moisture and temperature estimates from the 5th European reanalysis (ERA5-Land) dataset with in-situ measurements to assess the accuracy and applicability of ERA5-Land data for modelling the service life of wood in ground contact. The ERA5-Land soil temperature estimates showed a moderate correlation with the in-situ temperature measurements (Spearman’s ρ of 0.73) and a...
U Hundhausen, P B van Niekerk, B Marais
Determining the minimum water vapor permeability of exterior wood coatings by means of hygrothermal and decay models
2024 - IRG/WP 24-20717
The objective of this study was to determine the minimum water vapor permeability of exterior wood coatings for log homes using hygrothermal and decay modeling. The approach is based on a worst-case scenario assumption, namely a moisture trap at a given wood moisture content in a coated wall log. The minimum limit of vapor permeability of the coating system was determined by simulating the time re...
U Hundhausen, S Ullah, D Kraniotis
Fungal degradation of oak timber bridges
2025 - IRG/WP 25-11058
Wood is increasingly recognised as an eco-friendly building material, but its organic nature makes it vulnerable to degradation, especially in outdoor applications exposed to moisture. This study investigates wood-decaying fungi affecting oak timber bridges in Hanover, Germany. The study aimed to identify the fungal species using culture-independent methods and to examine the impact of poorly exec...
L Schrader, J Trautner, C Brischke
Moisture uptake in CLT during the construction phase: real construction conditions versus specimens exposed to environment
2025 - IRG/WP 25-41019
The rapid growth in the use of Cross-Laminated Timber (CLT) in construction highlights the need to address durability concerns, particularly in regions with less experience in Mass Timber Construction and favourable climatic conditions for the biological degradation of wood, such as Mediterranean countries. A lack of awareness and deficient construction management can negatively impact the public ...
D Lima, S Duarte, J M Branco, L Nunes (†)
Experimental characterizing of liquid water uptake and release – key to understand moisture-induced decay risk analysis
2025 - IRG/WP 25-41020
Wood can absorb water vapour (sorption) or liquid water (capillarity). Moisture from liquid water (rain, spray water) is often a problem for the performance of wood products used in outdoor structures. Wood is prone to biodegradation when is it too moist for too long periods. Experimental studies that allow conclusions to be drawn about the practical use of wood water uptake are limited due to the...
M Nopens, J T Benthien, J Trautner, C Brischke
Evaluation of moisture exclusion ability of wood using double-layer outdoor exposure tests
2025 - IRG/WP 25-41021
The material resistance of wood to decay must be due to the combined effects of heartwood extractives and the moisture content state. Evaluating the moisture exclusion ability of wood is important for assessing its durability in outdoor use. We conducted previously double-layer outdoor exposure tests and investigated the relationship between moisture content over time and the progress of decay usi...
T Osawa, R Noda, K Yamamoto