Your search resulted in 182 documents. Displaying 25 entries per page.
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
Frequency of fungal decay in softwood windows in Germany
2010 - IRG/WP 10-10725
Knowing how often fungal decay occurs is a fundamental basis for general recommendations of preservative measures. To optimize the German recommendations for chemical wood preservation of windows made out of pine or spruce more than 2000 windows have been inspected. All windows had an opaque coating and were between 2 and 17 years old. The selection of the inspected windows was kept as randomly as...
D Lukowsky, O Moarcas, A Luette
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
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
Effect of Coatings on the Durability of Birch and Spruce Plywood. Part 1: Weathering Performance
2010 - IRG/WP 10-40526
Several different coated birch and spruce plywood types were investigated in Finland using outdoor weathering. The weather performance of the tested coated birch plywood was good compared with uncoated birch and spruce plywood. The paint base film coated and painted birch plywood performed well in outdoor testing at VTT's test site. Phenol film coated plywood was sensitive to UV light, but on...
A Nurmi, H Viitanen
Effect of Coatings on the Durability of Birch and Spruce Plywood. Part 2: Biological Durability
2010 - IRG/WP 10-40527
Several different coated birch and spruce plywood types were investigated in Finland using the combination of outdoor weathering and decay test EN 12038. The most important factor to affect on the biological performance of birch plywood, coated and uncoated, was edge sealing. For spruce plywood edge sealing had a smaller effect. However, in spite of positive effect against decay, edge sealing did ...
A Nurmi, H Viitanen
A Review of Radial Flow of the Refractory Softwoods: An Example of Sitka Spruce
2011 - IRG/WP 11-40564
As one of the refractory softwood species, the major problems in the preservative treatment of spruce based on the radial flow relate to the anatomical structure of the wood material. The most important morphological features influencing this were the amount of the nature and the condition of both ray tracheids and ray parenchyma cells, and the cross-field pits in particular. The conducting pathwa...
Ilker Usta, Radovan Despot
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
Three-year field test of preservative-treated Canadian species in Korea
2014 - IRG/WP 14-30646
The purpose of this study was to generate field performance data in Korea on Canadian softwood species preservative-treated to Canadian standards. Two field tests of preservative-treated Canadian softwood species, one in ground contact and one above ground, were installed in Jinju, Korea in November 2010. Western hemlock and white spruce were incised and pressure-treated with alkaline copper quate...
Jieying Wang, Jong Bum Ra, P I Morris
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
Fire protection of wooden facades in Norway
2015 - IRG/WP 15-40710
Wood products are experiencing a renaissance as construction material in Europe due to their environmental benefits. In Norwegian building design however, timber has always played an important role but has had its limitations in urban architecture. One of the reasons is a high demand to fire safety in dense house building and multi-story buildings. Though novel construction methods and fire safety...
U Hundhausen, K-C Mahnert
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
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
Review on protection of timber bridges in Norway and other countries
2017 - IRG/WP 17-40809
Wood plays a major role in design and construction of modern bridges in Norway. Typical elements of those bridges are double impregnated glued laminated members, stress laminated timber decks, slotted-in steel plates, metal cladding of the surfaces of loadbearing members, and cross girders made of steel. Selected examples of timber bridges in Norway are presented. This review paper gives an overvi...
K-C Mahnert, U Hundhausen
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
Moisture and temperature conditions in an old, highly moisture-loaded timber building in the Røros municipality, Norway
2020 - IRG/WP 20-10966
A 150 years old log building near Røros, Norway, has been in active use as a cowshed since its erection. The animals are kept inside the cowshed all winter and this causes a situation of a high moisture load on the wooden floor, wooden walls and ceiling. Logging of temperature and humidity over one year shows that there are favourable levels of moisture in the wood and air for development of moul...
M Sand Austigard, J Mattsson
Performance of a water-borne stain on beech, spruce, MDF and OSB improved by plasma pre-treatment
2020 - IRG/WP 20-40897
Coatings are an important part of wood protection, especially for outdoor applications. In order to provide a good protection, protective coatings need to exhibit good adhesion, mechanical resistance, and weathering resistance. Plasma pre-treatments are an established method to increase the performance of existing coatings including those on wood and wood-based substrates. Moreover, plasma deposit...
S Dahle, J Žigon, I Uranjek, M Petrič
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