Durability and protection of timber structures in marine environments in Europe: An overview

Timber structures in marine applications are often exposed to severe degradation conditions caused by mechanical loads and wood-degrading organisms. This paper presents the use of timber in marine environments in Europe from a wood protection perspective. It discusses the use of wood in coastline protection and archeological marine wood, reviews the marine borer taxa in European waters, and gives an overview of potential solutions for protection of timber in marine environments. Information was compiled from the most relevant literature sources with an emphasis on new wood protection methods; the need for research and potential solutions are discussed. Traditionally, timber has been extensively utilized in a variety of marine applications. Although there is a strong need for developing new protection systems for timber in marine applications, the research in this field has been scarce for many years. New attempts to protect timber used in marine environments in Europe have mainly focused on wood modification and the use of mechanical barriers to prevent colonization of marine wood borers. The importance of understanding the mechanisms of settlement, migration, boring, and digestion of the degrading organisms is key for developing effective systems for protecting timber in marine environments.

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Macrobiological Degradation of Esterified Wood with Sorbitol and Citric Acid

Forests ◽

10.3390/f11070776 ◽

2020 ◽

Vol 11 (7) ◽

pp. 776 ◽

Cited By ~ 1

Author(s):

Andreas Treu ◽

Lina Nunes ◽

Erik Larnøy

Keyword(s):

Citric Acid ◽

Marine Environment ◽

Field Trials ◽

Wood Products ◽

Choice Test ◽

Subterranean Termites ◽

Protective Properties ◽

Wood Modification ◽

Wood Protection ◽

Marine Applications

There is a need for new solutions in wood protection against marine wood borers and termites in Europe. A new solution could be the esterification of wood with sorbitol and citric acid (SCA) since these are inexpensive and readily available feedstock chemicals and have shown protective properties against fungal wood degradation in earlier studies and prevented macrobiological degradation, as shown in this study. Protection of wood products in the marine environment lacks available wood preservatives that are approved for marine applications. Termite infestation is opposed mainly by biocide treatments of wood. Several wood modification systems show high resistance against both marine borers and subterranean termites. However, the existing commercialized wood modification products are costly. Both macrobiological forms of degradation represent a great threat for most European wood species, which are rapidly and severely degraded if not properly treated. This study investigated esterified wood in standard field trials against marine wood borers, and against subterranean termites in laboratory trials in a no-choice and choice test. The treatment showed good resistance against wood borers in the marine environment after one season and against subterranean termites in the laboratory after eight weeks. The low termite survival rate (SR) in the no-choice test during the first week of testing indicates a mode of action that is incomparable to other wood modification treatments.

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Bacteriophage can drive virulence in marine pathogens

Marine Disease Ecology ◽

10.1093/oso/9780198821632.003.0004 ◽

2020 ◽

pp. 73-82 ◽

Cited By ~ 1

Author(s):

Mark Little ◽

Maria Isabel Rojas ◽

Forest Rohwer

Keyword(s):

Pathogenic Bacteria ◽

Bacterial Pathogens ◽

Meta Analysis ◽

Relevant Literature ◽

Marine Ecosystems ◽

Marine Environments ◽

Human Pathogens ◽

Large Role ◽

Associated Bacteria ◽

And Function

The roles of prophages in disease have mainly considered human pathogens, while their role in marine pathogens has only recently been considered. This chapter reviews the relevant literature on what is known of prophages in marine ecosystems and provides a meta-analysis of the abundance and function of prophages in marine pathogenic bacteria. According to these results, bacterial pathogens in marine environments contain a significantly higher abundance of prophage DNA in their genomes than host-associated bacteria, which are non-pathogenic. The authors also surveyed the genetic content of the prophages that were associated with known pathogens and compared their functions to non-pathogens. Their findings suggest that horizontally acquired prophage-encoded DNA may play a large role in the ecology and evolution of marine diseases

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A Review of Wood Modification Globally – Updated Findings from COST FP1407

Interdisciplinary Perspectives on the Built Environment ◽

10.37947/ipbe.2020.vol1.1 ◽

2020 ◽

Vol 1 ◽

Author(s):

Dennis Jones ◽

Dick Sandberg

Keyword(s):

Environmental Impact ◽

Commercial Production ◽

Thermal Modification ◽

The Other ◽

Current Status ◽

Wood Modification ◽

Wood Protection ◽

Extensive Evaluation ◽

Online Sources ◽

Modified Wood

Wood modification (chemical, thermal, impregnation) represents an assortment of innovative processes continually being adopted in the wood protection sector. COST Action FP1407 “Understanding wood modification through an integrated scientific and environmental impact approach — ModWoodLife” was initiated in 2015, with its 4-year programme aiming to investigate modification processing and products design with emphasis on their environmental impacts. Among the final tasks within COST FP1407 was to re-evaluate the current status of wood modification across the member countries. However, it became clear that activities in other European countries needed to be addressed, and as a result, a more extensive evaluation of wood modification processes across Europe was undertaken, as well as determining the activities globally. This paper outlines some of the recent updates in wood modification, along with summarising data collected by the authors from international colleagues and online sources, so providing an evaluation of the overall global position. These figures suggest that wood modification is undergoing a significant increase in production due to demand, with levels of recent growth seemingly suggesting this will continue for the coming years. Based on data gathered, the global commercial production of modified wood is dominated by thermal modification processes, which produce 1,110,000 m3/year. Among the other commercialised processes, acetylation accounts for 120,000 m3/year and furfurylation 45,000 m3/year. A further global production of around 330,000 m3/year is estimated for other processes, predominantly based on resin-based systems (e.g., Impreg- and Compreg-based processes).

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Defensive strategies of Norway spruce and Kurile larch heartwood elucidated on the micron-level

Scientific Reports ◽

10.1038/s41598-021-01590-y ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Sophie Füchtner ◽

Sara Piqueras ◽

Lisbeth Garbrecht Thygesen

Keyword(s):

Norway Spruce ◽

Cell Types ◽

Environmentally Benign ◽

Water Regulation ◽

Data Decomposition ◽

Wood Protection ◽

Final Destination ◽

Defensive Strategies ◽

Protection Systems ◽

Different Origin

AbstractTo decarbonize the building sector, the use of durable wood materials must be increased. Inspiration for environmentally benign wood protection systems is sought in durable tree species depositing phenolic extractives in their heartwood. Based on the hypothesis that the micro-distribution of extractives influences durability, we compared the natural impregnation patterns of non-durable, but readily available Norway spruce to more durable Kurile larch by mapping the distribution of heartwood extractives with Confocal Raman Imaging and multivariate data decomposition. Phenolics of both species were associated with hydrophobic oleoresin, likely facilitating diffusion through the tissue. They accumulated preferentially in lignin-rich sub-compartments of the cell wall. Yet, the distribution of extractives was found not to be the same. The middle lamellae contained flavonoids in larch and aromatic waxes in spruce, which was also found in rays and epithelial cells. Spruce-lignans were tentatively identified in all cell types, while larch-flavonoids were not present in resin channels, hinting at a different origin of synthesis. Larch-oleoresin without flavonoids was only found in lumina, indicating that the presence of phenolics in the mixture influences the final destination. Together our findings suggest, that spruce heartwood-defense focuses on water regulation, while the more efficient larch strategy is based on antioxidants.

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Multi-Jackbolt Tensioner Type Expansion Bolts for Marine Applications

10.5957/pss-2009-14 ◽

2009 ◽

Author(s):

Stephen J. Busalacchi

Keyword(s):

Finite Element Method ◽

Finite Element ◽

Shear Test ◽

Marine Environments ◽

Interference Fit ◽

Thrust Bearings ◽

Removal Time ◽

Load Carrying ◽

Marine Applications ◽

Element Method

This paper introduces and discusses the multi-jackbolt tensioner (MJT) type expansion bolt with split expanding sleeve as a replacement to standard fitted or interference fit bolts that are widely used within industry, including navy and marine environments. For marine uses, applications include shaft and propulsion coupling bolting as well as on anchoring and positioning bolting often required for most line shaft bearings, thrust bearings, and steering gears. Both a Finite Element Method (FEM) study and a shear test were recently performed to confirm superior load carrying ability as compared to standard fitted bolts. Further, results of these tests, installation / removal time comparisons, and calculated costs savings are presented here for consideration.

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Comparative Aboveground Performance of Pressure-Treated Copper Azole with Alternative Wood Protection Systems under Subtropical Conditions

Forest Products Journal ◽

10.13073/fpj-d-20-00023 ◽

2020 ◽

Vol 70 (3) ◽

pp. 335-339

Author(s):

Matthew J. Konkler ◽

Gerald Presley ◽

Jeffrey J. Morrell

Keyword(s):

Surface Treatments ◽

Pressure Treatment ◽

Fungal Decay ◽

Wood Protection ◽

Rigorous Testing ◽

Protection Systems ◽

Termite Attack ◽

Silica Treatment ◽

Copper Azole ◽

Insect Attack

Abstract The performance of several wood surface treatments as well as a silica treatment claiming to provide protection against fungal decay and termite attack in aboveground applications were examined in termite, ground proximity, and sandwich tests at a subtropical site near Hilo, Hawaii. In general, the surface treatments performed similarly to untreated controls and provided little or no protection against fungal or insect attack. The silicate treatment provided some termite and decay protection, but fungal decay resulted in rapid declines in condition after 50 to 54 months of exposure. Copper azole–treated lumber provided the best performance against both termites and fungal attack, illustrating the benefits of pressure treatment over surface treatments in high-decay-hazard environments. These results also illustrate the importance of rigorous testing and standardization protocols for any product that makes durability claims before it enters the market to ensure that it will perform as expected.

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