Durabilité du bois à la mer. Utilisation d’essences alternatives de bois durables pour les ouvrages maritimes et côtiers
Résumé
Les bois tropicaux sont utilisés dans les ouvrages maritimes et côtiers. Des caractéristiques élevées (durabilité, résistance mécanique, résistance à l’abrasion, résistance aux xylophages, …) sont requises dans ce type d’environnement. Certains bois tempérés pourraient atteindre le niveau requis, mais uniquement s’ils étaient traités industriellement. La récente législation européenne a restreint le nombre de traitements utilisables dans le milieu maritime. De plus, il y a un souci général sur le caractère potentiellement néfaste de ces produits pour l’environnement. Les retours sur la performance en service de certaines essences sont bons. Ainsi, les maîtres d’œuvre ou les entreprises tendent à limiter leur choix à celles-ci, notamment l’azobé et le greenheart, ce qui accroît la pression sur ces seules essences. La recherche conduite de 2007 à 2009 par Environment Agency, TRADA, HRWallingford et le CETMEF a permis d’identifier une liste d’essences de bois à partir de bases de données. Cette liste a ensuite été progressivement réduite à partir d’essais innovants de qualification de la résistance à l’usure et la résistance aux xylophages (en laboratoire et in situ). Enfin des caractéristiques en vraie grandeur ont été déterminées pour cinq essences.
Abstract:
Tropical hardwoods are used in coastal and maritime structures. High level of characteristics and performance (durability, strength, resistance to abrasion, resistance to marine borers…) are expected in such environments. Some softwood of Europe could meet the requirement but only if they were treated industrially. There is some concern that preservatives may be harmful to the environment and the recent legislation however limits their use in the marine environment. Feed-back from experience of exposure to service conditions is good for some hardwoods. Hence, designer and contractors tend to limit their choice to these only timbers, in particular greenheart and ekki. Consequently, the sustainability of the use of these only species is questionable. The research conducted from 2007 to 2009 by Environment Agency, TRADA, HRWallingford and CETMEF identified a list of species from available database, which was progressively reduced thanks to innovative tests to assess resistance to abrasion and to marine borers attack (laboratory tests and field tests). Finally, the full-scale strength of five species was determined.
Keywords: Coastal structures; Maritime structures; Timber; Marine borers; Abrasion; Ekki; Greenheart
Mots-clés
Texte intégral :
PDFRéférences
AITKEN & HOWARD LTD. (2007). List of commercially available hardwood timber that could form suitable alternative to greenheart and ekki. Aitken and Howard project communication.
BIODIVERSITY INTERNATIONAL (2007). Study into alternatives to greenheart and ekki tropical hardwood timber. Environment Agency, Unpublished report, pp 1–40.
BOLZA E., KEATING W.G. (1972). African timbers – the properties, uses and characteristics of 700 species. Division of Building Research, Commonwealth Scientific and Industrial Research Organisation, Australia.
BORGES L.M.S., CRAGG S.M., WILLIAMS J.R. (2003). Comparing the resistance of a number of lesser known species of tropical hardwoods to the marine borer Limnoria using a short term laboratory assay. International Research Group on Wood Preservation, Report IRG/WP 03.
BRAZIER J. (1995). Greenheart and the choice of timbers for marine work. Notes from the half day meeting at the maritime board of the Institution of Civil Engineers on the 3rd October, pp 1-12.
CHUDNOFF M. (1979). Individual data sheets for species by region of origin: Africa: tropical timbers of the world. Forest Products Laboratory, Forest Services, United States Department of Agriculture.
CROSSMAN M., SIMM J.D. (2004). Manual on the use of timber in coastal and river engineering. Thomas Telford, London. CrossRef
DUPRAY S.W., SIMM J.D. (2007). Climate change : materials and material uses. The edge – The magazine of coastnet, winter edition, pp 14–15.
ECOCHOICE (2007). List of commercially available hardwood timber that could form suitable alternative to greenheart and ekki. Ecochoice project communication.
GOLLASH S. (2006). Teredo navalis – data sheet. EU project DAISIE.
GREEN M., PITMAN A.J. (2001). A preliminary study of timber susceptibility to attack by the weevil Euophryum confine (Broun). Proceeding of the 5th International Conference on the Development of Wood Science, Wood Technology and Forestry, Ljubljana, Slovenia.
HALL G.S., SAUNDERS R.G. (1967). Incidence of marine borers around Britain’s Coast. Timber Research and Development Association, High Wycombe, Report B/RR/4.
MAINIERI C., CHIMELO J.P. (1989). Fichas de caracteristicas das Madeiras Brasileiras. Instituto de Pesquisas Tecnologicas Divisão de Madieras, São Paulo.
MAUN K. (2000). Handbook of hardwoods. Building Research Establishment Press.
METTEM C.J., RICHENS A.D. (1991). Hardwoods in construction. Timber Research and Development Association, High Wycombe.
NEWTON A., MUDGE S.M. (2003). Temperature and salinity regimes in a shallow, mesotidal lagoon, the Ria Formosa, Portugal. Estuarine, Shelf and Coastal Science, Vol. 57, pp 73–85. CrossRef
N’GUYEN M.N., LEICESTER R.H., WANGA C.H., COOKSONB L.J. (2008a). Probabilistic procedure for design of untreated timber piles under marine borer attack. Reliability Engineering & System Safety, Vol. 93, n° 3, pp 482–488. CrossRef
N’GUYEN M.N., LEICESTER R.H., WANG C. (2008b). Marine borer attack on timber structures - Manual n° 7. Commonwealth Scientific and Industrial Research Organisation, Vistoria, Australia.
NICHOLLS R.J., DE LA VEGA LEINERT A.C. (2008). Implications of sea-level rise for Europe’s coasts: an introduction. Journal of Coastal Research, Vol. 24, n° 2, pp 285 287. CrossRef
OLIVER A.C. (1974). Timber for marine and fresh water construction. Timber Research and Development Association, High Wycombe.
RAPP A., BROSCHKE C., WELZBACHER C.R. (2007). The influence of different soil substrates on the service life of Scots pine sapwood and oak heartwood in ground contact. Wood Material Science and Engineering, Vol. 2, n° 1, pp 15–21. CrossRef
SAWYER G.S., WILLIAMS J.R. (2005). An investigation to assess the feasibility of developing an accelerated laboratory test to determine the abrasion resistance of lesser-used timber species for use in marine construction. International Research Group on Wood Preservation, Report IRG/WP 05.
SIMM J.D., WALLIS M.J., COLLINS K.J., ATKINS R. (2004). Re-use of materials in coastal and river engineering. Proceedings of the Institution of Civil Engineers, Engineering sustainability, Vol. 157, n° 3, pp 113–121. CrossRef
WILLIAMS J.R. (1999). Factors affecting the performance of antisapstain preservatives in the field. PhD thesis, Department of Biology, Imperial College, London.
WILLIAMS J.R., SAWYER G.S., CRAGG S.M., SIMM J.D. (2004a). A questionnaire survey to establish the perceptions of UK specifiers concerning the key material attributes of timber for use in marine and fresh water construction. International Research Group on Wood Preservation, IRG/WP 04.
WILLIAMS J.R., CRAGG S.M., BORGES L.M.S., ICELY J.D. (2004b). Marine exposure assessment of the natural resistance of a number of lesser-known species of tropical hardwoods to teredinid and limnoriid borers. International Research Group on Wood Preservation, IRG/WP 04.
WILLIAMS J.R., MEADEN M., SIMM J., DUPRAY S. (2010). Assessment of the durability and engineering properties of lesser-known hardwood timber species for use in marine and freshwater construction. TRADA -Timber Research and Development Association- Technology Ltd., Environment Agency and HR Wallingford Ltd. URL Adress
DOI: http://dx.doi.org/10.5150/revue-paralia.2014.s01
Renvois
- Il n'y a présentement aucun renvoi.
_ISSN 1760-8716_
© Editions Paralia CFL