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Monday, 15 August 2016

Molecular and Cell Wall Structure of Wood

Published Date
Volume 3 of the series NATO Conference Series pp 7-51

Title 

Molecular and Cell Wall Structure of Wood

  • Author 
  • Richard E. Mark

Abstract

To the materials scientist, the word “fiber” connotes a slender, thread-like structure with substantial mechanical properties. The term includes a vast array of natural and synthetic materials — derived from metals, polymers, ceramic and vitreous materials, and from diverse animal and plant origins. Wood is a fibrous material in the main. In the woods produced by conifers, some 90 per cent of the volumetric composition and approximately 95 per cent of the dry mass can be attributed to cellulosic fibers known as tracheids. Lignified cellulosic fibers of various kinds form the bulk of virtually all woods. Accordingly, our attention focuses on the constituent fibers when we consider the material wood from a materials science standpoint. In wood as well as in other plant-derived materials, the fibers are in reality the exoskeletons of once-living, elongate cells that originated from a meristem. The cells each have a lumen, or hollow center.

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For further details log on website :
http://link.springer.com/chapter/10.1007/978-1-4684-8983-5_2

Wood

Published Date
Date: 

Title 

Wood

  • Author 
  • Helena Cruz 
  • Dennis Jones
  • Lina Nunes

Abstract

The growing diversity of wood products and their uses contradicts the idea that wood is a traditional material, which has always been used by humans with a minimum of modification, widely known and still mainly processed on an empirical knowledge basis. Since wood is a natural material, there is a plethora of information about its production, about the forestry concerns in environmental terms and the wood’s value within the context of sustainability of the construction. Given the objectives of this publication, this chapter would cover mainly the aspects that can more directly help engineers and architects regarding the use of wood in construction. Together with a basic knowledge of the material, which is considered indispensable, a point has been made to provide guidelines for the selection of wood and its application in the construction industry.

References

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    Machado JS, et al (2009) Madeira como Material Estrutural. In: Avaliação, Conservação e Reforço de Estruturas de Madeira. Verlag Dashöfer, Lisbon: pp. 5–22
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    Forest Products Laboratory (1999) Wood Handbook: Wood as an engineered material. Gen. Tech. Rep. FPL–GTR–113. United States Department of Agriculture, Madison, WI, p. 463
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    Machado JS (1996) Madeiras de Folhosas e Resinosas. Nomenclatura Comercial. ITES 11. LNEC, Lisbon, p 64
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    NP 180, Anomalias e Defeitos da Madeira. IPQ, Lisbon
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    EN 942, Timber in joinery—general classification of timber quality. CEN, Brussels
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    NP 4305, Madeira Serrada de Pinheiro Bravo para Estruturas—Classificação Visual. IPQ, Lisboa
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    LNEC (1997) Pinho bravo para estruturas.. Madeira para Construção—Ficha M2. Lisbon, LNEC
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    Carvalho A (1996) Madeiras Portuguesas. Vol.1: Estrutura Anatómica, Propriedades, Utilizações. Instituto Florestal. p. 340
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    EN 13183-1, Moisture content of a piece of sawn timber. Part 1: determination by oven dry method. CEN, Brussels
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    LNEC (1997) Especificação de Madeira para Estruturas. Madeira para Construção—Ficha M1. LNEC, Lisbon
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    Nunes L (2008) Termite infestation risk in Portuguese historic buildings. Cost Action IE0601 «Wood Science for Conservation of Cultural Heritage». Braga, Portugal, 5 a 7 de Novembro de 2008. Online http://​www.​woodculther.​org/​
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    Nunes L et al (2010) First records of urban invasive Cryptotermes brevis (Isoptera: Kalotermitidae) in continental Spain and Portugal. J Appl Entomol 134:637–640. doi:10.​1111/​j.​1439-0418.​2009.​01490.​x
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    EN 460, Durability of wood and wood-based products. Natural durability of solid wood. Guide to the durability requirements for wood to be used in hazard classes. CEN, Brussels
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    EN 351-1, Durability of wood and wood-based products preservative-treated solid wood. Part 1: classification of preservative penetration and retention. CEN, Brussels
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    EN 351-2, Durability of wood and wood-based products. Preservative-treated solid wood. Part 2: guidance on sampling for the analysis of preservative-treated wood. CEN, Brussels
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    EN 599-1, Durability of wood and wood-based products. Efficacy of preventive wood preservatives as determined by biological tests. Part 1: specification according to use class. CEN, Brussels
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    Machado JS (2005) Placas de Derivados de Madeira. Tipos de Placas e sua Especificação. Informação Técnica de Estruturas, ITES 14. LNEC, Lisbon, p 96
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    EN 312, Particleboards. Specifications. CEN, Brussels
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    EN 622-1, Fibreboards. Specifications—Part 1: general requirements. CEN, Brussels
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    EN 636, Plywood. Specifications. CEN, Brussels
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    EN 12369-1, Wood-based panels. Characteristic values for structural design—part 1: OSB, particleboards and fibreboards. CEN, Brussels
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    EN 12369-2, Wood-based panels. Characteristic values for structural design—part 2: plywood. CEN, Brussels
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    EN 12369-3, Wood-based panels. Characteristic values for structural design—part 3: solid-wood panels. CEN, Brussels
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    EN 14080, Timber structures. Glued laminated timber and glued solid timber. Requirements. CEN, Brussels
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    Cruz H (2007) Estruturas de Madeira Lamelada colada em Portugal. Instrumentos para a Garantia da Qualidade. Revista Portuguesa de Engenharia de Estruturas, Série II 1:45–56
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    EN 1194, Timber structures. Glued laminated timber. Strength classes and determination of characteristic values. CEN, Brussels
  36. 36.
    EN 14374, Timber Structures. Structural Laminated Veneer Lumber. Requirements. CEN, Brussels

For further details log on website :
http://link.springer.com/chapter/10.1007/978-3-319-08236-3_12

From Present Researches to Future Developments

Published Date
Date: 

Title 

From Present Researches to Future Developments

  • Author 
  • Voichita Bucur

Abstract

Delamination phenomena in manmade composites (Tay 2003, Sridharan 2008) as well as in wood and wood-based composites have received much attention from scientists and practitioners due to serious technological implications and obvious scientific curiosity for this subject.

References

  1. Freund LB (1998) Dynamic fracture mechanics. Cambridge University Press, Cambridge
  2. Lemaitre J, Desmorat R (2005) Engineering damage mechanics. Springer, Berlin, Heidelberg
  3. Ravi-Chandar K (2004) Dynamic fracture. Elsevier, Amsterdam
  4. Sridharan S (ed) (2008) Delamination behaviour of composites. Woodhead Publishing, Cambridge
  5. Tay TE (2003) characterization and analysis of delamination fracture in composites: an overview of development from 1991 to 2001. Appl Mech Rev 56:1–31CrossRef

For further details log on website :
http://link.springer.com/chapter/10.1007/978-90-481-9550-3_20

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