Your search resulted in 558 documents. Displaying 25 entries per page.
Underground timber constructions from the First World War are well preserved after 100 years
2017 - IRG/WP 17-10897
During the Great War or World War I many underground constructions have been built for protection from shelling. They were an important part of the trench warfare as they were used as an area to rest and carry out other activities such as eating. They would usually range in size from smaller constructions that could hold several men to larger entities that could hold thousands of soldiers. In the ...
J Van Acker, I De Windt, K Haneca, H Beeckman, F Claeys, S Vandenbussche, J Vandewalle, N Robeyst, A Willems
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
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
Comparative Durability of Timber Bridges in the USA
2017 - IRG/WP 17-20615
As engineers begin to utilize life-cycle-cost design approaches for timber bridges, there is a necessity for more reliable data about their durability and expected service life. This paper summarizes a comprehensive effort to assess the current condition of more than one hundred timber highway bridge superstructures throughout the United States. This national study was jointly administered by the ...
J P Wacker, B K Brashaw
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
Prefacricated modular wooden bridges
2017 - IRG/WP 17-40785
The bridge consists of simple, identical pre-fabricated triangular wooden panels joined top and bottom to make up trusses. These trusses are in turn joined together side by side in pairs and are braced to one another to create a girder construction. The deck is carried on top of the trusses, an arrangement which has several advantages for such an uncomplicated structure. It is built up on site, af...
L Jayanetti
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
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
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
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
Evaluation of the Virulence of the Termite Species Occurring in the French Tropical Overseas Territories
2018 - IRG/WP 18-10913
The French tropical overseas territories are strongly affected by termites’ activity, which is especially devastating because the species encountered there are among the most virulent in the world. That is why in these regions it is particularly important that producers and users of wood-based products are provided with materials and preservative products whose durability and efficacy has been t...
M Kutnik, I Paulmier, J Vuillemin
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
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
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