Your search resulted in 504 documents. Displaying 25 entries per page.
Consistency of performance of acetylated wood
2017 - IRG/WP 17-20608
It is well known that acetylation of wood improves the resistance against wood decaying fungi and insects, as well as its dimensional stability under varying moisture conditions. Accsys Group continues to support a variety of laboratory and field studies around the world to assess and monitor the durability, dimensional stability and uniformity of its products. To gain and maintain market acceptan...
F Bongers, J van Zetten
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
Overview of the treated wood quality control program in the United States with the recent challenges and advances
2017 - IRG/WP 17-20616
In the past two decades, there have been significant and rapid changes in wood protection technologies for residential applications which have moved away from long established heavy duty metal oxide based products such as chromated copper arsenate (CCA). The successor generation of wood protection systems usually contain copper as the primary biocide, in combination with carbon-based co-biocides s...
L Jin
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
New Standards for Approval of Modified Wood within the Nordic Wood Preservation Council (NWPC)
2017 - IRG/WP 17-20624
In the Nordic countries, there is a long tradition for quality labelling of preservative treated wood. Until now the labelling has been restricted to pine and other easy to treat wood species, but with the introduction of a new set of standards it is now possible to obtain the Nordic Wood Preservation Council’s (NWPC) quality labelling also for modified wood.
In this paper, we will introduce th...
N Morsing, E Engelund Thybring, M Klamer
Ensuring Quality of Treated Wood – Regulations, Certifications and Associative Background in the Field of Wood Protection in Europe
2017 - IRG/WP 17-20626
Beside legal requirements, buyers and end-users of wood preservatives and/or of treated wood and wood-based materials may require additional warranties regarding the quality and the performance of the products available on the market. These greatly enhance the confidence of end-users and the chance for a product of being marketed with a quality label. Additionally, quality control systems and trai...
M Kutnik, M Klamer, E Melcher
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
Markers of quality in self-bonded beech boards
2017 - IRG/WP 17-40820
A self-bonding phenomenon takes place when five layers of beech (Fagus Sylvatica L.) veneers are pressed at temperatures higher than 200ºC. If the pressing temperature between veneer surfaces reaches at least 225ºC during pressing and if the pressure applied is optimal, water-resistant bonds are formed between veneers. This study investigates the relation of thickness reduction (marker of compre...
C Cristescu, D Sandberg, O Karlsson
Wood chemistry completes natural durability as criteria for shorting best provenances in the improvement of teakwood quality: case of five provenances from Ivorian Séguié’s trial
2018 - IRG/WP 18-10920
In order to determine the best provenance for continuing breeding program in Côte d’Ivoire, five provenances of teak planted in 1970 at Séguié’s trial (Agboville, in the south of Côte d’Ivoire), were compared. Fifteen trees (three trees per provenance) composed the sample. Decay resistance and the chemical content especially, non-structural carbohydrates, total phenolics and quinone comp...
F B Niamke, N Amusant, A A Adima, A A Kadio, G Chaix, C Jay-Allemand
The Impact of Cryopreservation Techniques and of Water Quality on the Wood Degrading Ability of Fungal Strains: Recommendations for Maintenance and Culturing Procedures
2018 - IRG/WP 18-20636
In order to establish an optimal cryopreservation method, strains of Basidiomycete and Ascomycete fungi, which are among the most frequently used for wood durability testing, were evaluated using three cryopreservation procedures at -80°C. The main objective was to prevent decrease of the fungal virulence that may occur due to repeated routine sub-culturing procedures and to optimize the reactiva...
A Stum, M Montibus, I le Bayon, M Kutnik
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
In-line quality control of the film thickness in industrial coating processes for exterior cladding
2018 - IRG/WP 18-40835
The production of industrially coated wood cladding has been strongly increasing in Scandinavia during the last years. In the beginning of this development, industrial coating processes included solely the application of pigmented primers; these however provide only a short protection of the wood surface and the application of a top coat is required during the first 6 to 12 months after mounting t...
U Hundhausen, M Slabohm
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