Robinia Specifications
Robinia:
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Scientific name: Robinia pseudoacaia
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Commercial restriction: no commercial restriction
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Note: originates from the east of the USA. Was introduced into Europe and is grown commercially in Southeastern Europe between Hungry and Romania.
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Natural Durability & Treatability:
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Fungi and termite resistance refers to end-user under temperate climate. Except for special comments on sapwood, natural durability is based on mature heartwood. Sapwood must always be considered non-durable against wood degrading agents.
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Funghi (E.N. standards): class 1-2 - very durable to durable
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Dry wood borers: durable - risk limited to sapwood
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Termites (E.N. standards): class D - durable
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Treatability (E.N. standards): class 4 - resistant
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Use class ensured by natural durability: class 4 - in ground or fresh water contact
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Species covering the use of class 5: no
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Note: this species is listed in the European standard EN 350-2. It is the only temperate hardwood introduced in Europe which naturally covers the use class 4.
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Requirement of a Preservative Treatment:
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Against dry wood borer attacks: does not require any preservative treatment
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In case of risk of temporary humidification: does not require any preservative treatment
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In case of risk of permanent humidification: does not require any preservative treatment
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Log Description:
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Diameter: from 50mm to 500mm
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Thickness of sapwood: thin band
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Log durability: good
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Mechanical & Acoustic Properties:
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Crushing strength: 70 MPa
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Static bending strength: 126 MPa
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Modulus of elasticity: 16900 MPa
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(at 12% moisture content with 1 MPa = 1 N/mm2)
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Fire Safety:
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Thickness > 14 mm : M.3 (moderately inflammable)
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Thickness < 14 mm : M.4 (easily inflammable)
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Euroclass grading: D s2 d0
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Notes: default grading for solid wood, according to requirements of European standard EN 14081-1 annex C. It concerns structural graded timber in vertical uses with mean density upper 0.35 and thickness upper 22 mm.
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British Standard EN 350-2 Durability of wood and wood-based products — Natural durability of
solid wood:
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Natural Durability:
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A five class system is used for durability:
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very durable
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durable
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moderately durable
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slightly durable
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not durable
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The durability given in the tables refers to heartwood only; sapwood of all wood species should be considered as belonging to durability class 5 (not durable).
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The ability of wood to absorb moisture has an important effect upon its service life in out-of-ground contact, and service life in these situations depends on both its durability class and its treatability class. A wood of a given durability which has low moisture absorbing characteristics (for example treatability class 4) will, because of reduced water uptake, generally last markedly longer in out-of ground contact situations, which are subject to intermittent wetting, than a wood of the same durability rating, but which is more absorbent (for example treatability class 1).
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Natural Durability to Termites:
A three class system is used:
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D - Durable
M - Moderately Durable
S - Susceptible
The durability refers to heartwood only; sapwood of all wood species is susceptible.
Natural Durability to Marine Borers:
A three class system is used:
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D - Durable
M - Moderately Durable
S - Susceptible
The durability refers to heartwood only; sapwood of all wood species is susceptible.
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Treatability:
A four class system is used and is based on a vacuum/pressure treatment processes.
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permeable (easy to treat)
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moderately resistant (moderately easy to treat)
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resistant (difficult to treat)
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extremely resistant (difficult to treat)
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Sapwood/Heartwood:
Typical sapwood width is given to indicate its abundance in mature trees and is categorized as follows:
VS - very small (< 2 cm)
S - small (2 cm to 5 cm)
M - medium (5 cm to 10 cm)
B - broad (> 10 cm)
The durability and the treatability of sapwood and heartwood are usually different with higher durability in the heartwood and better treatability in the sapwood.
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