Spremembe fizikalnih lastnosti hrastovega lesa iz zgodovinskih konstrukcij v življenjski dobi

Straže, Aleš (author), Dremelj, Matjaž (author), Žveplan, Ervin (author), Čufar, Katarina (author)

Raziskali smo fizikalne lastnosti hrastovega lesa (Quercus sp.), pri katerem je od poseka minilo od 4 do 512 let in smo ga razdelili v stoletne starostne skupine 100-600. Mlajši les smo pridobili ob poseku dreves, starejši les pa iz zgodovinskih konstrukcij v Sloveniji. Izbrani les smo najprej dendrokronološko datirali, izdelali normirane vzorce za analize ter določili gostoto, barvo, dimenzijsko stabilnost in sorpcijske lastnosti. Vizualno in v CIELab barvnem prostoru smo ugotovili, da je barva jedrovine s starostjo postala temnejša. Pri starem hrastovem lesu smo ugotovili tudi manjšo higroskopnost in izboljšano dimenzijsko stabilnost, zlasti v tangencialni smeri, ter manjšo prečno krčitveno anizotropijo.Gostota hrastovega lesa se s staranjem ni spremenila, odvisna pa je bila od širine branik (naraščala je z večanjem deleža kasnega lesa). Rezultati nakazujejo, da na dimenzijsko stabilnost in higroskopnost poleg procesov staranja ver-jetno vpliva tudi mesto vgradnje in klimatska nihanja tekom uporabe lesa.

• Language: Slovenian
• Keywords: les, hrast, lesena gradnja, Quercus sp., staranje, barva, dimenzijska stabilnost, sorpcija
• Work type: Article
• Typology: 1.01 - Original Scientific Article
• Organization: BF - Biotechnical Faculty
• Publication status: Published
• Publication version: Version of Record
• Year: 2018
• Number of pages: Str. 5-14
• Numbering: Letn. 67, št. 1
• PID: 20.500.12556/RUL-126670
• UDC: 630*814.7:630*812
• ISSN on article: 0024-1067
• COBISS.SI-ID: 2921609
• Publication date in RUL: 03.05.2021

STRAŽE, Aleš, DREMELJ, Matjaž, ŽVEPLAN, Ervin and ČUFAR, Katarina, 2018, Spremembe fizikalnih lastnosti hrastovega lesa iz zgodovinskih konstrukcij v življenjski dobi. Les [online]. 2018. Vol. 67, no. 1, p. 5–14. [Accessed 18 May 2025]. Retrieved from: https://repozitorij.uni-lj.si/IzpisGradiva.php?lang=eng&id=126670

Record is a part of a journal

• Title: Les
• Shortened title: Les
• Publisher: Zveza društev inženirjev in tehnikov gozdarstva in lesarstva Slovenije, Zveza društev inženirjev in tehnikov gozdarstva in lesarstva Slovenije, Biotehniška fakulteta, Oddelek za lesarstvo, Založba Univerze, Biotehniška fakulteta, Oddelek za lesarstvo, Založba Univerze
• ISSN: 0024-1067
• COBISS.SI-ID: 13940224

Licences

• License: CC BY 4.0, Creative Commons Attribution 4.0 International
• Link: http://creativecommons.org/licenses/by/4.0/
• Description: This is the standard Creative Commons license that gives others maximum freedom to do what they want with the work as long as they credit the author.
• Licensing start date: 01.06.2018

Secondary language

• Language: English
• Title: Changes in physical properties of oak wood from historical constructions during service life

Abstract

We examined the physical properties of oak wood (Quercus sp.) felled four to 512 years ago, grouped in age groups of 100-600 years. The wood originated from recently felled trees and from historical constructions in Slovenia. The selected wood was dendrochronologically dated. We made standardized samples and determined wood density, colour, dimensional stability and sorption properties. Visual and CIELab analyses showed that the colour of the heartwood became darker with age. Historical oak wood was characterised by lower hygroscopicity and higher dimensional stability, especially in the tangential direction, as well as reduced transverse shrinkage anisotropy compared to recently felled wood. The density of oak wood did not change with age, it was dependent on tree-ring widths and the proportion of latewood, and increased along with the proportion of latewood. Besides ageing, the location of wood during its service life and exposure to climate fluctuations also seemed to influence the dimensional stability and hygroscopicity of historical oak.

• Keywords: oak, wood, ageing, colour, hygroscopicity, dimensional stability, sorption

Projects

• Funder: ARRS - Slovenian Research Agency
• Project number: P4-0015
• Name: Les in lignocelulozni kompoziti