Your search resulted in 3115 documents. Displaying 25 entries per page.
Changes in hygroscopic, mechanical and surface properties of Scottish-grown Sitka Spruce (Picea sitchensis) wood subjected to dry heat treatment
2008 - IRG/WP 08-40415
Heat-treatment is a wood modification method which has been used to some extent in improving timber quality. However, the main limitation in the use of this technique despite its numerous advantages is the adverse effects on the various properties associated with the use of wood as an engineering material. Dry heat treatment of Scottish-grown Sitka spruce (Picea sitchensis) wood was carried out at...
L Awoyemi, M C Jarvis, A Hapca
Effects of CCB on wood strength of Eastern spruce (Picea orientalis L.)
2008 - IRG/WP 08-40416
The effects of CCB (chromate copper boron) on the static bending properties of Eastern spruce (Picea orientalis L.) based on MOE (modulus of elasticity) and MOR (modulus of rupture) were evaluated after full-cell vacuum/pressure treatment using a 3.0 % concentration followed by kiln-drying at 15 and 30 % moisture contents with heating the preservative at 30 and 40 ºC. The results showed that MOE ...
I Usta, M Hale
Comparison of permeability at different levels of moisture content in Bornmullerian fir (Abies bornmulleriana Mattf.) and Eastern spruce (Picea orientalis L.) impregnated under vacuum/pressure through full-cell method by using CCA and CCB of different concentrations
2007 - IRG/WP 07-40366
In this study, a comparison has been made in terms of the combined, longitudinal, tangential, and radial permeability of the species of Bornmullerian fir (Abies bornmulleriana Mattf.) and Eastern spruce (Picea orientalis L.) with moisture contents of 50 % and 15 %, which were impregnated under vacuum/pressure through full-cell method by using water-borne wood preservatives (impregnation materials)...
I Usta
A review of Sitka spruce (Picea sitchensis (Bong.) Carr.) as its Importance and Breeding
2010 - IRG/WP 10-10717
Foresters tend to concentrate on those species which are the easiest to handle silviculturally, and which will produce the greatest volume of generally useful wood in the shortest time. Sitka spruce (Picea sitchensis (Bong.) Carr.), which is a softwood species from the western seaboard of North America with a range extending from southern Alaska to northern California, is one of the pioneer specie...
I Usta, R Despot
Study of Microscopy Properties of Modified Wood During Weathering Process
2010 - IRG/WP 10-40517
In this study spruce (Picea excelsa) and Beech (Fagus orientalis) wood acetylated and has been subjected of artificial weathering in difference times (0, 50,150&300 h), then wood surface analyzed using Scanning Electron Microscopy (SEM). The SEM results shown that the surface of wood exposed to weathering undergoes distinct physical changes and the surface degradation appears to be directly propor...
M Akhtari
Adsorption boundary curve influenced by step interval of relative humidity investigated by Dynamic Vapour Sorption equipment
2011 - IRG/WP 11-40547
The adsorption of water vapour from dry conditions by Norway spruce sapwood has been investigated using Dynamic Vapour Sorption (DVS) instrumentation. This equipment allows a fast and easy data acquisition as well as enables detailed studies of sorption properties using very small sample masses. In this study, particular focus was paid to the effect of step size on the sorption isotherms. Furtherm...
E Tang Engelund, M Klamer, T Mark Venås
Field-testing of Norway Spruce Claddings with Monitoring of Moisture Content, Material Temperature and Microclimate
2012 - IRG/WP 12-20502
The physical function of a cladding is to protect the interior construction. Under normal circumstances the performance requirements can be met for a very long time, meaning that the technical service life of a wooden cladding can be very long. Since the cladding is a major part of the facade, it also has visual requirements that may define the aesthetic service life, and often it is much shorter ...
G I Vestøl, L Ross Gobakken
Water absorption and desorption of non treated, pressure impregnated, and pine oil treated glulam made of small diameter Scots pine and Norway spruce
2012 - IRG/WP 12-40616
A growing proportion of harvested timber originates from the first or second commercial thinning stands in Finland, which means smaller average log volumes in comparison to final felling stands. Smaller log volume means challenging wood properties such as higher proportion of juvenile wood and sapwood. Due to these facts, products made of small diameter logs are prone to twist and check, and have ...
H Heräjärvi, V Möttönen, R Stöd
The influence of microclimate on the moisture conditions in a Norway spruce (Picea abies (L.) Karst.) joint exposed to artificial rain
2013 - IRG/WP 13-20505
Wood structures outdoors are susceptible to decay if they are exposed to high moisture contents during long periods of time. Structures with joints that act as water traps are especially exposed since high moisture contents are reached in such positions. This paper presents a part of a laboratory study that concerns the relationship between the microclimate and the material climate, i.e. the moist...
M Fredriksson, L Wadsö, P Johansson
Mould growth on spruce claddings and the effect of selected influencing factors after 4 years of outdoor testing
2015 - IRG/WP 15-30671
Norway spruce (Picea abies) is the most frequently chosen wood species as claddings in façades in Norway, and is used both coated and uncoated. The visual changes that occur during weathering can be colour changes, abrasion or wear, blistering, flaking, and even cracks in the wood or coating, but more often growth of mould and blue stain fungi is the main challenge. A field test with synchronous monitoring of relative humidity, air temperature, material temperature and wood moisture content in Norway spruce claddings has been performed in southern Norway as part of the ClimateLife project. Visual evaluation of blue stain and mould growth according to EN 927-3 was performed, and evaluation data after 46 months exposure is presented. The objectives were to study the effect of 1) environment, 2) cardinal direction and 3) colour of the coated surface on growth of blue stain and mould fungi and to study the variation in relative humidity, air temperature, wood moisture content and material temperature. After 46 months exposure, the red coating system had generally the lowest mould ratings and the uncoated claddings had the highest. Of the white coloured claddings the ones facing south had lower mould ratings than those facing north, but the opposite were found for red coloured claddings. The relative humidity was higher in front of claddings exposed northwards and in a shaded environment compared to an open environment against south. In an open environment red coloured claddings had the lowest wood moisture content and highest material temperature, and red coloured claddings against south had the highest maximum material temperature.
L Ross Gobakken, G I Vestøl
Investigation of enzymatic effect on pit membranes by light and scanning electron microscopy
2016 - IRG/WP 16-40721
Spruce wood, one of the refractory wood species has pit membranes, which has an influence on the permeability of wood providing liquid flow between the wood cells. However, these membranes tend to close under the fiber saturated point (FSD), which makes impregnation more difficult. In this study spruce sapwood samples were treated with two different commercial enzymes to improve the permeability o...
S Durmaz, Ü C Yildiz, M Öztürk, B Serdar
Creosote leaching from timber bridges in Norway – a practical classification approach
2016 - IRG/WP 16-40744
Creosote is widely used as a wood preservative for highway timber bridges in Norway. However, excessive creosote leaching at various highway timber bridge sites leads to a bad reputation for the use of creosote treated timber constructions and the use of wood in general. Macro- and micro anatomical factors such as amount of heartwood, annual ring width, annual ring orientation, ray- height and com...
A Treu, K Zimmer
Improvement of wood properties by impregnation with liquefied spruce bark based resins
2016 - IRG/WP 16-40761
In this paper, biobased phenolic thermosetting resins are designed to be used as wood stabilization treatment. The originality of the study stands in substituting part of phenol by spruce (picea abies) bark: this is achieved by a liquefaction process in phenol in the presence of sulfuric acid as catalyst. Next, thermosetting resins are synthetized from liquefied bark by condensation on formaldehy...
X Duret, E Fredon, E Masson, P Gérardin
Performance of Norway spruce bridge in North-West Spain after 12 years exposure
2017 - IRG/WP 17-40796
Across Europe is very common to find bridges build in sawn and glue-laminated wood. Most of these bridges used softwood wood species such as: fir, spruce, larch and pine.
In Spain wooden bridges, became more and more popular since nineties, when sawn and glue-laminated wood were utilized for building exterior wooden structures in overall Spain.
This material, sawn and glue-laminated wood, are ma...
D Lorenzo, J Fernández-Golfín, M Touza, M Guaita, A Lozano, J Benito
The Effects of Pre-Microwave Treatment on Retention Levels And Some Mechanical Properties of Spruce Wood Treated with CCA
2017 - IRG/WP 17-40800
Microwave (MW) treatment of wood has been evaluated in recent years for different purposes by several scientists. Microwave conditioning improves permeability, reduces density and heat conductivity and changes dimensional stability. Furthermore, it could even improve the permeability of refractory wood species such as spruce and Douglas fir. In this study, MW pre-treatment was applied to spruce wo...
E D Gezer, S Kuştaş, S Durmaz
Decay resistance of beams made from thermally modified Scots pine and Norway spruce after 6 years’ exposure in ground contact
2017 - IRG/WP 17-40806
In the present study the resistance of beams treated by ThermoWood® process was studied in ground contact and the results given are based on a “modified” EN 252 test. After six years’ exposure clear differences were found between untreated Scots pine and Norway spruce beams and treated ones. In all cases thermal modification improved the performance. Thermally modified pine heartwood showed...
S Metsä-Kortelainen, H Viitanen
How carbon stored in harvested wood products contribute in a greenhouse gas accounting perspective
2017 - IRG/WP 17-50327
In 2014 the net annual removal by Norwegian forests was 30.4 mill ton CO2-eqvivalents while the emissions in other sectors was 53.2 mill ton CO2-eqvivalents. Hence, forests can play a major role in the national greenhouse gas balance. But forests also contribute to the carbon pool stored in wood products. The aim of this paper is, by using Norway as an example, to illustrate how the greenhouse gas...
G Alfredsen, G Søgaard
Premature failure of wood structures in Use Class 3 caused by decay - some examples from Norway
2018 - RG/WP 18-20643
The Nordic Wood Preservation Council (NWPC) has since 1976 had a standard for classification of preservative treated wood, documents describing conditions for approval of preservatives for industrial use and requirements for quality control of preservative treated wood. Last year, 2017, the NWPC extended the quality system to include natural durability (heartwood) and modified wood.
The objecti...
P-O Flaete
Monitoring uptake and penetration of pesticides during impregnation of pine (Pinus sylvestris) and spruce (Picea abies) wood with bio-based microemulsion gel formulations
2020 - IRG/WP 20-30756
Even in dry state wood is susceptible to biological degradation. Preservation against biological decay in exposed conditions is conventionally achieved by impregnating the wood with pesticides applied at professional and industrial levels. Impregnation of wood with preservatives is a complex process that involves wood macro- and microstructure, and the physical characteristics of woods. Here we fo...
D Messaoudi, K Ruel, J-P Joseleau
Is cascading of harvested wood products really an environmentally beneficial strategy in Finland and Norway?
2020 - IRG/WP 20-50364
The role of cascading wood waste in the bioeconomy is highlighted in the several strategic documents. The European Waste Framework Directive describes a waste hierarchy where re-use and recovery are considered more favourable options compared with energy recovery, and applies strict re-use and recycling targets to household waste and non-hazardous construction and demolition waste. It is not fully...
C A S Hill, G Alfredsen, M Hughes, L R Gobakken
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
Performance of wood exterior structures above ground in Spain. Performance and durability of a shelter of spruce in a shopping centre after 20 years
2022 - IRG/WP 22-20680
Across Europe is very common to find wood exterior structures mainly build in sawn and glue-laminated wood. Most of these exterior wood structures use softwood wood species such as: fir, spruce, pine or douglas. In Spain exterior wood structures, became more and more popular since nineties, when sawn and glue-laminated wood were utilized for building exterior wood structures in overall Spain. In m...
D Lorenzo, A Lozano, M Alonso, J Fernández-Golfín, M Touza, J Benito
Analysis of wooden shingles after seven years of exposure
2022 - IRG/WP 22-20690
Wood is a traditional roofing material in the Alpine regions. In the 17th century, wooden roofing was typically used on more important buildings. Still, today it is predominately used on huts and houses in the hilly regions of northern and north-western Slovenia. Because wooden roofing is expensive, we investigated the possibility of extending the service life of the roofing through impregnation a...
M Humar, B Lesar, D Kržišnik, E Keržič, B Jemec
A new project - Circular use of wood in Norway for improved sustainability and innovation (CircWOOD)
2022 - IRG/WP 22-50369
In Norway, around 12 m3 timber are logged each year. If our society is to succeed in reducing its greenhouse gas emissions, it is expected that the need for resources will be significantly greater than that. Recycled wood will be a crucial input factor through new reuse and material recycling solutions. In order to close knowledge gaps related to the availability and quality of recycled wood, the ...
L Ross, L Huang, E Trømborg, R Modaresi, H Sjøli, C A S Hill
Short-term absorption of water and coatings on thermally modified blue-stained spruce wood
2023 - IRG/WP 23-40984
The importance of wood has been increasing in the last decades. Among conifers, predominantly spruce (Picea abies) wood is often used in building constructions in Europe. Namely for construction and facades of buildings, decking and fences. Due to the increased public concerns about biocides, alternative techniques for protection, such as thermal modification and protection by construction, are ga...
R Hasanagic, M Bahmani, M Humar, L Fathi, L Cai