Your search resulted in 499 documents. Displaying 25 entries per page.
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
The iTrussT project – Advancements in timber bridge design, preservation, and monitoring
2025 - IRG/WP 25-20751
The Norwegian research project iTrussT (2025–2028) aims to advance timber bridge design and unlock wood’s full potential as a sustainable solution for modern infrastructure. It addresses three critical challenges: First, fatigue testing of glued laminated timber lamellae will provide deeper insights into shear failure mechanisms, supporting the development of safer, more efficient structures a...
K-C Mahnert, U Hundhausen
Premature failure of treated timber in wharfs in Papua New Guinea, attributed to defects in design
1991 - IRG/WP 4158
The performance of timber in wharfs in Papua New Guinea has been monitored for a number of years. Premature failure of wharf structures was found in many cases to be due to defects in design rather than ineffective preservative treatment. Above-water timbers were found to be prone to severe checking followed by decay. Protection for the end grain of pile tops and the limiting of radial checking in...
S M Cragg
Monitoring a Timber Bridge in Norway
2004 - IRG/WP 04-40282
We have instrumented three different timber bridges in Norway for the Norwegian Public Roads Administration. The goal was to learn more about the properties of timber bridges. We have instrumented Evenstad Bridge, Daleråsen Bridge and the last year Flisa Bridge. All bridges are have creosoted glulam trusses and creosoted stress laminated deck. Evenstad and Flisa have an asphalt deck on top, while...
F G Evans
The Development of a novel method to preserve reeds using an environmentally friendly timber preservative and a unique engineering design.
2006 - IRG/WP 06-40335
Reeds are used in the construction of bush lodges in Northern Kwa- Zulu Natal, South Africa. Fungal, insect and ultra-violet damage to these reeds is posing a severe problem. Within a space of two years, the reeds are attacked and have to be subsequently replaced; a time consuming and costly exercise. A novel method has been used to successfully preserve these reeds with an environmentally friendl...
K Govender, K G Moodley
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
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
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
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
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
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
Timber reuse and circularity: Insight from Norway's SirkTre and CircWOOD initiatives
2025 - IRG/WP 25-50409
Timber is central to the EU’s decarbonisation strategy, particularly in the building sector, which faces challenges related to climate adaptation, resource constraints, and rising costs. The four-year SirkTRE project aims to improve circularity in the timber industry by developing standards, promoting reuse, and expanding market opportunities. A key focus of SirkTRE is to increase the longevity ...
K Nore, L Ross
Solvent drying and preservation of timber
1977 - IRG/WP 381
Processes which combine drying and preservation are first reviewed. Some preliminary experiments are then described in which blocks of green Sitka spruce sapwood were immersed, in a solution of tributyltin oxide (TBTO) in methanol at 60°C. Satisfactory penetration of the preservative and exchange of methanol and water occurred in a few hours. The methanol was removed rapidly from the wood by evap...
J A Petty
Screening potential preservatives against stain and mould fungi on pine timber in Zimbabwe
1995 - IRG/WP 95-30063
The search for environmentally and toxicologically safer chemicals for use in the timber preservative industry against stain and mould fungi has been intensified during the past few years. Results of field tests with two chemicals previously evaluated in the laboratory are presented. The conventional sodium pentachlorophenate was the more efficacious chemical against stain and mould fungi, providi...
A J Masuka
IRG/COIPM INTERNATIONAL MARINE TEST - to determine the effect of timber substrate on the effectiveness of water-borne salt preservatives in sea-water. Progress Report 2: Report of treatment and installation in Australia
1978 - IRG/WP 440
The purpose of this test and the procedures to be followed have been fully set out in documents distributed by the International Research Group on Wood Preservation and numbered IRG/WP/414 and IRG/WP/420. The prescriptions set out in these two documents have been closely followed....
J Beesley
Manual of a mini treating plant for waterborne preservative treatment of timber and bamboo
1999 - IRG/WP 99-40130
This contributional article includes machinaries and equipments necessary for a small wood treating plant for the pressure treatment of tim bers with waterborne preservatives along with the cost and design. The preservative treatment limitations, treatment schedules and specifications for different products have been described. The cost of a mini treating plant will be 6,00,000 Tk. (13,000 US$), s...
A K Lahiry
Field performance of wood preservative systems in secondary timber species
1997 - IRG/WP 97-30152
The objective of this ongoing study is to evaluate the performance of new, potential, and standard wood preservative systems in secondary North American timber species. Eleven preservative systems were evaluated in this study - ACQ Type B, Copper Citrate 2: l, CDDC, chlorothalonil/chlorpyrifos, copper-8-quinolinolate, tebuconazole/chlorpyrifos, RH287, propiconazole/chlorpyrifos, copper naphthenate...
P E Laks, K W Gutting, R C De Groot
IRG/COIPM INTERNATIONAL MARINE TEST - to determine the effect of timber substrate on the effectiveness of water-borne salt preservatives in sea-water. 2nd Interim Report
1981 - IRG/WP 477
Three reference wood species - Alstonia scholaris, Fagus sylvatica and Pinus sylvestris, untreated and treated with 3%, 6% and 10% CCA and CCB solutions were supplied to all participants for submergence at local sites. Regular examination of samples is being carried out - 6 months, 12 months and then annually for 7 years....
R A Eaton
Report an some aspects of forest and the timber preservation in Fiji 1999
2000 - IRG/WP 00-40189
This report is divided in two sections. One is the general description of some aspects of the Forest indicating timber availability in Fiji. The other Section is an "Status of Timber Preservation in Fiji in 1999"....
S D Kumar
IRG/COIPM INTERNATIONAL MARINE TEST - to determine the effect of timber substrate on the effectiveness of water-borne salt preservatives in sea-water. Progress Report 10 from Naos Island, Panama
1980 - IRG/WP 462
Blocks of 3 wood species, Beech (Fagus sylvatica), Scots pine (Pinus sylvestris) and Alstonia (Alstonia scholaris) were exposed at site number 12 at Naos Island, Panama on March 8, 1978 by John R. DePalma. The arrangement of the panels in the exposure site is as shown in Figure 1....
D W French
An evaluation method for less termite attack execution on thermal insulation for fundation walls
2002 - IRG/WP 02-20245
According to the results by the real scale Japanese building tests, the termite installation was observed at very little spaces between foundation and insulation. The termite penetration spaces between foundation and insulation on foundation systems in Japanese wooden houses were checked by the way of streaming speed of colored water. Because of difficulty for its execution, the parts of outside a...
K Suzuki, Y Tanaka
Electrodialytic remediation of creosote and CCA treated timber wastes
2002 - IRG/WP 02-50190
There is a growing concern about the environmental issue of impregnated timber waste management, since an increase in the amount of waste of treated wood is expected over the next decades. Presently, no well-documented treatment technique is yet available for this type of waste. Alternative options concerning the disposal of treated wood are becoming more attractive to study, especially the ones ...
E P Mateus, A B Ribeiro, L Ottosen
IRG/COIPM INTERNATIONAL MARINE TEST - to determine the effect of timber substrate on the effectiveness of water-borne salt preservatives in sea-water. Progress Report 13: Report of fourth inspection (36 months) in Australia
1981 - IRG/WP 481
This report presents the results of the fourth inspection of the IRG/COIPM International Marine Test specimens installed in Sydney Harbour in December, 1977. The inspection took place on 9th December, 1980, after 36 months exposure. Full details of the treatment and installation of the specimens, as well as results of the first three inspections (after 6, 12, and 24 months exposure), have been pre...
J Beesley