Your search resulted in 448 documents. Displaying 25 entries per page.
Case study: “Riesenbühlturm”
2017 - IRG/WP 17-20599
In this case study four 7 m long Douglas fir crossbeams were investigated regarding the remaining metal and moisture content. The crossbeams were replaced from a timber tower after 10 years of service in the Black Forest region (South Germany) due to fungal decay. From each of the crossbeams five stem discs were taken and relevant parameters (density, moisture and remaining metal content) were de...
E Melcher, J Müller
Design and performance prediction of timber structures based on a factorization approach
2017 - IRG/WP 17-20603
Service life of timber structures in outdoor conditions is predominantly affected by the climatic conditions in terms of moisture and temperature over time. On the one hand, the two parameters moisture content and temperature determine the exposure-induced dosage that can lead to fungal infestation and subsequent decay. On the other hand, the material resistance of wood stands in opposition to exp...
L Meyer-Veltrup, C Brischke
Laboratory test to determine the effect on durability of combining biobased building materials with timber in construction
2017 - IRG/WP 17-20604
The use of Structural Insulated panels is a construction approach that is seeing more abundant use and is becoming a widely available method. Preformed units are usually a composite structure which often include a range of bio-based materials such as timber, wool or straw. Traditional laboratory based wood decay tests do not take into account this combination of biobased materials and it may be po...
S F Curling, G A Ormondroyd
Moisture content as a quality control parameter in thermally modified timber production
2017 - IRG/WP 17-20622
Quality assurance (QA) or factory production control (FPC) is necessary to ensure a proper production process. The requirements of QA/FPC can result from EN and national standards, quality assurance systems, or producer-specific rules.
TMT producers must ensure that the process was correct, and to ensure traceability of products. In addition to the electronic records, the material should be che...
W Scheiding, H Turkulin, S Stein
An experimental study of mould growth and wood decay in timber frame walls
2017 - IRG/WP 17-20623
This paper deals with parameters related to the occurrence of mould growth and wood decay in timber frame walls. In a first part, the hygrothermal conditions inside a timber frame wall finished with brick veneer cladding are analysed to get an idea of possible moisture related problems. It is shown that, based on the VTT mould prediction model, there is a mould risk on the interface between the in...
M Vanpachtenbeke, J Van den Bulcke, I De Windt, J Langmans, S Roels, J Van Acker
Efficacy of Erythropleum suaveolens (potrodom) and Distemonanthus benthamianus (bonsamdua) water extractives on the durability of five Ghanaian less used timber species of varying perviousness and retentiveness
2017 - IRG/WP 17-30705
Conventional wood preservatives are not only toxic to target bio-deterioration organisms but also to humans, other organisms and the environment. In an effort to find preservatives that are less toxic or non-toxic to man, other organisms and the environment, efficacy of branch bark and heartwood water extracts (0.65 g/ml) of Erythropleum suaveolens (potrodom) and Distemonanthus benthamianus (bonsa...
A Asamoah, K Frimpong-Mensah, C Antwi-Boasiako
Copolymers of tannin extracts as wood protection agents
2017 - IRG/WP 17-30709
Wouldn´t be a dream to preserve wood with the substances which the nature already synthesizes for protecting itself? The idea we would like to pursue is simple: Increase the concentration of these substances, the tannins, trying to fix them properly in wood. It appears easy but it is not. Sensibility against leaching, fungal decay and weathering were observed. In this paper new flavonoid co-polym...
G Tondi, L Sommerauer, A Oberle, A Petutschnigg, M-F Thevenon
Evaluation of timber bridges with special consideration of detail design
2017 - IRG/WP 17-40781
Since 1997 the use of wood in bridge construction has been increasingly criticized by the Hamburg federal state authority supposedly because of shortened service life due to decay. With regard to wood research, however, it is often suggested that use of timber is suitable for weathered structures as long as constructive protection measures will be observed. In order to unravel the reasons for the ...
K Robbers, J Fromm, E Melcher
Solid Timber Bridges – Latest Developments
2017 - IRG/WP 17-40788
The technology of gluing in wood construction has evolved considerably in recent years. This has been shown especially in timber bridges that Glulam is now the main building material. A further development is the so-called block gluing, which provides a good basis for supporting structures. Numerous bridges, especially in central Europe, appeal by unique design and monolithic and solid construction. These structures base on two main developments: block lamination of glulam and the composite of timber and concrete to one structural system.
F Miebach
The potential and the challenges of acetylated wood in timber bridges - experiences from an ongoing project
2017 - IRG/WP 17-40792
Acetylated wood is known to be a durable and dimensional stable alternative for high performance materials, and has high potential for exterior timber structures. Research has shown that acetylated wood can be effectively bonded by various adhesive types. However, one of the most common used adhesives for timber constructions, Melamine Urea Formaldehyde (MUF), shows a high degree of delamination o...
A Treu, R Bredesen, F Bongers
In-service performance of treated plywood bridge decks in Australia
2017 - IRG/WP 17-40794
Engineered wood products have a long history of use in bridge construction in Australia. The first bridges incorporating chemically protected engineered wood components were installed in the 1850’s and some survive to this day. Preservative treated plywood bridge deck panels have been employed since the 1980’s as a replacement for the more traditional hardwood plank decks. This paper report...
M A Powell
Borate and Copper Naphthenate Dual Treatment of Bridge Timbers-Borate movement over time
2017 - IRG/WP 17-40795
Preservative treated wooden bridge ties in the South Eastern USA have a service life of about 15 to 20 years, which falls well below the average service life of 40 years of railroad cross ties (sleepers). It has been shown that cross tie life is significantly extended using borate dual treatment and this is now commercialized in bridge timbers using borate inserts. In previous research, it was dem...
J-W Kim, J D Lloyd
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
Dual Borate and Copper Naphthenate Treatment of Bridge Timbers:- Potential Performance Enhancements and Cost Savings
2017 - IRG/WP 17-40797
Dual treatment technology combining diffusible preservatives with oil borne preservatives, widely used for crossties in the USA, has now also been commercialized with bridge ties/timbers. In order to understand the implications of these changes, the historic service life of creosote treated bridge timbers in northern and southeastern USA were considered as well as field test data for both creosote...
J Lloyd, C Brischke, R Bennett, A Taylor
A summary of history and use of timber bridges in New Zealand
2017 - IRG/WP 17-40801
Wooden bridges have been an important part of road and rail networks in New Zealand. While wooden structures have largely been replaced by concrete and steel on major arteries they still have a place where lightweight, easily assembled structures are needed. These timber bridges may also be a cheaper alternative to other materials in roads which carry relatively low traffic loads. In the last ten ...
D Page, T Singh
Durability of energy efficient wooden buildings: a building physical point of view
2017 - IRG/WP 17-40812
The drive for more energy efficient and sustainable buildings resulted in an increased popularity of wooden buildings, even in countries with a masonry tradition. Often guidelines and prescriptions then are copied from other countries. Different climatic boundary conditions and tradition of finishing, though, do require different moisture tolerance criteria. This is clearly the case for water vapo...
S Roels, J Langmans
Corrosion verification experiment of the screw driven into CLT
2017 - IRG/WP 17-40816
Japan has abundant forest resources, but we depend on import for 70 percent of the consumed timber. Japan has the vision which promotes the timber self-sufficiency rate 30% to 50% by 2020. Therefore CLT attracts attention as a new timber material. Japan has a climate with high temperature and humidity, and wooden buildings are often treated with chemicals as a measure against biological deteriorat...
N Wada, H Ishiyama, S Yamamoto
Influence of sea water on timber and metal joints
2017 - IRG/WP 17-40818
In the Great East Japan Earthquake that occurred in March 2011, many buildings suffered from seawater immersion caused by the tsunami. Saito's study revealed that corrosion progresses on metal plate that experienced seawater immersion 1). However, the detailed mechanism of corrosion progresses has not yet been clarified. Therefore, in this study, salinity which is one of causes of corrosion w...
T Nishimura, H Ishiyama, F Hirose, N Wada
Testing the durability of timber products above ground using the block-test method – A critical review
2018 - IRG/WP 18-20637
The block-test method for testing the durability of wood and wood products above ground is reviewed critically with respect to practical aspects, moisture loads, corresponding decay development, and the possibilities of assessing test specimens by determining the dynamic modulus of elasticity (MOEdyn) of wood. In total, 36 blocks representing different modifications of the original set-up and a wi...
C Brischke, A Gellerich, H Militz
Self-Extinguishment Phenomena of Mass Timber in Medium-Scale Compartment Fires
2018 - IRG/WP 18-30729
This paper presents a review of the fire safety risks that mass timber construction may introduce in buildings, with special consideration to medium- and high-rise buildings. These main risks are represented by an effect to the classical fire safety strategy for buildings: (1) Compartmentalisation, to ensure that the fire will not spread farther than the compartment of origin, (2) Preventing verti...
C Gorska, J P Hidalgo
Performance of wood exterior structures above ground in Spain built with softwood species. The situation case of a shelter bridge
2018 - IRG/WP 18-40844
Across Europe is very common to find wood exterior structures build in sawn and glue-laminated wood. Most of these exterior wood structures use softwood wood species such as: fir, spruce, larch and pine. 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. This paper s...
D Lorenzo, M Touza, J Fernández-Golfín, A Lozano, J Benito
Thermally modified timber treated with methacrylate
2018 - IRG/WP 18-40849
Thermally modified timber (TMT) from Scots pine sapwood similar to Thermo-D quality was impregnated with methacrylate resin by the hot-and-cold method and subsequently cured at elevated temperatures. The results showed that methacrylate resin could be used to reduce colouring of painted TMT wood during accelerated weathering probably by hindering the migration of extractives. The resin itself did ...
O Karlsson, O Myronycheva, DJones, D Elustondo, D Sandberg
Determining the natural durability on xylarium samples: mini-block test, wood powder and chemical profiling
2019 - IRG/WP 19-10944
Xylaria, or wood collections, can be considered sleeping beauties in terms of wood technological and biological output. In this study we focus on determining the natural durability of xylarium specimens from the Federal Xylarium in the Royal Museum for Central Africa. The Federal Xylarium contains over 80,000 specimens, covering more than 13,000 species, mainly from Central Africa. These specimens...
V Deklerck, L De Ligne, J Van den Bulcke, E Espinoza, H Beeckman, J Van Acker
Validation by micro-computed tomography of an assessment method to measure the residual strength of anobiids infested timber
2019 - IRG/WP 19-20650
In this article a quantitative correlation study of pine timber structural elements, which have been subject to attack by anobiids, is presented. The main objective of the study was to establish a valid empirical correlation between the lost material percentage (consumed by beetles) and original/residual apparent density. Since the beetles’ attack produces a diffuse damage with a set of tunnels ...
J L Parracha, M F Pereira, A Maurício, P Faria, L Nunes
Visual assessment of longitudinal wheel timbers and assessing the feasibility of extending wheel timber service life in the UK railway network
2019 - IRG/WP 19-20651
Timber has been a versatile building material for centuries and during the start of the Railway Age in the nineteenth century it was in considerable demand for use in the railway network, particularly bridge building. Timber is still in service and widely used throughout the UK railway network. The resilience and favourable strength to weight ratio and its relative ease of fabrication make it an...
J R Williams