Publications
NIBIOs employees contribute to several hundred scientific articles and research reports every year. You can browse or search in our collection which contains references and links to these publications as well as other research and dissemination activities. The collection is continously updated with new and historical material.
2017
Abstract
Creosote is commonly used as a wood preservative for highway timber bridges in Norway. However, excessive creosote bleeding at various highway timber bridge sites lead to complaints, and a potentially bad reputation for wooden timber bridges. Macro-and microanatomical factors such as the amount of heartwood, annual ring width, annual ring orientation, ray-height and composition and resin canal area were investigated in order to classify seven timber bridges in Norway into bleeding- and non-bleeding bridges. A classification into bleeding and non-bleeding was possible for discriminant categories based on three anatomical factors analysed on wood core samples. The amount of heartwood content dominated the influencing factors, even obscuring the significance of other factors. Classification with a low amount of variables was done preferably on sample level instead of bridge level, due to the restricted number of 17 core samples per bridge.
Abstract
No abstract has been registered
Authors
Signe Kynding Borgen Gry Alfredsen Johannes Breidenbach Lise Dalsgaard Gunnhild Søgaard Aaron SmithAbstract
No abstract has been registered
Authors
Signe Kynding Borgen Gry Alfredsen Johannes Breidenbach Lise Dalsgaard Gunnhild Søgaard Aaron SmithAbstract
No abstract has been registered
Abstract
No abstract has been registered
Authors
Lise Dalsgaard Aaron Smith Ryan Bright Gunnhild Søgaard Gry Alfredsen Signe Kynding Borgen Johannes BreidenbachAbstract
No abstract has been registered
2016
Abstract
No abstract has been registered
Abstract
Wood protection against fungal decay is mainly based on chemical protection. Nontoxic protection methods have become more important in Europe due to environmental concerns. A method using electric fields to inhibit wood decay by fungi has been investigated in laboratory trials and wood mass loss and moisture content after exposure to fungal attack were determined. The results show significantly reduced mass loss for wood samples exposed to a low pulsed electric field (LPEF), while wood samples connected to alternating and direct current displayed higher mass loss compared to LPEF. Changing the electrode material reduced the mass increase due to metal ion transfer into the wood samples for LPEF-exposed samples. The use of conductive polymer instead of metal electrodes and carbon fibers was preferable as no ions were transferred and the integrity of the material persisted. Decay of pre-exposed wood samples to white rot could be stopped or slowed down by means of LPEF.
Abstract
There is an increasing awareness of how the aesthetical performance of wood exposed outdoors changes over time and especially in the first few years after installation. Mould and blue stain fungi are biological agents that contribute to the weather grey colour on a wooden façade, and the blue stain fungi Aureobasidium pullulans is commonly identified as colonizer on coated and uncoated wood exposed outdoors. In this study 21 wood substrates (untreated, preservative treated and modified) were tested for their susceptibility to A. pullulans when incubated at three different temperatures (11, 16 and 22°C). Western red cedar and preservative treated wood had the lowest mould ratings at the end of the test period (84 days). Alder, ash, Norway spruce and Sitka spruce reached maximum rating already at day 28, and at day 84 also aspen, European larch, thermally modified pine, birch, acetylated pine and DMDHEU modified pine had reached maximum rating. Incubation temperature had a significant influence on the growth of A. pullulans throughout the test period for acetylated and DMDHEU modified samples – and generally the modified wood substrates were more sensitive to changes in temperature than the other tested substrates. Scots pine sapwood seemed to be less susceptible to A. pullulans in mono cultures, demonstrating low mould ratings throughout the test period. This contradicts to previous studies were Scots pine sapwood tended to have high susceptibility when using a mix of mould and blue stain fungi.
Abstract
No abstract has been registered