Prediction of timber twisting based on measured spiral grain of spruce trunks and logs

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F68378297%3A_____%2F23%3A00575777" target="_blank" >RIV/68378297:_____/23:00575777 - isvavai.cz</a>

Výsledek na webu

<a href="https://doi.org/10.52202/069179-0108" target="_blank" >https://doi.org/10.52202/069179-0108</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.52202/069179-0108" target="_blank" >10.52202/069179-0108</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Prediction of timber twisting based on measured spiral grain of spruce trunks and logs

Popis výsledku v původním jazyce

This work focuses on the prediction of timber (beam) twisting based on the measurement of spiral grain under the bark of spruce trees (using Fakopp) and the subsequent measurement of spiral grain of logs during manipulation using a slope of grain detector. When selecting wood, it is necesary to take account of the effect of spiral grain on sawings - based on international practice - a spiral grain up to 5% deviation per 1 m of log length is not considered a defect. However, it is important whether the spiral is left-handed or right-handed, as measured on the log perimeter. Left-handed spiral increases after log processing while right-handed spiral decreaces. The perimeter of an element from a left-handed log that was within the acceptable 5% angle deviation per 1 m of length manifests a considerably higher deviation when machined, when markedly affects the timber twist during drying. By contrast, beams from right-handed logs with up to 5% deviation per 1 m of length have perimeter without spiral grain, and they are not defected by twist during drying. This phenomenon has been confirmed by the study conducted. Further, a good prediction of spiral grain in trees has been achieved using non-invasive equipment, Fakopp ArborSonic Microsecond Timer.

Název v anglickém jazyce

Prediction of timber twisting based on measured spiral grain of spruce trunks and logs

Popis výsledku anglicky

This work focuses on the prediction of timber (beam) twisting based on the measurement of spiral grain under the bark of spruce trees (using Fakopp) and the subsequent measurement of spiral grain of logs during manipulation using a slope of grain detector. When selecting wood, it is necesary to take account of the effect of spiral grain on sawings - based on international practice - a spiral grain up to 5% deviation per 1 m of log length is not considered a defect. However, it is important whether the spiral is left-handed or right-handed, as measured on the log perimeter. Left-handed spiral increases after log processing while right-handed spiral decreaces. The perimeter of an element from a left-handed log that was within the acceptable 5% angle deviation per 1 m of length manifests a considerably higher deviation when machined, when markedly affects the timber twist during drying. By contrast, beams from right-handed logs with up to 5% deviation per 1 m of length have perimeter without spiral grain, and they are not defected by twist during drying. This phenomenon has been confirmed by the study conducted. Further, a good prediction of spiral grain in trees has been achieved using non-invasive equipment, Fakopp ArborSonic Microsecond Timer.

Druh

D - Stať ve sborníku

CEP obor

—

OECD FORD obor

20102 - Construction engineering, Municipal and structural engineering

Projekt

<a href="/cs/project/GA21-29389S" target="_blank" >GA21-29389S: Experimentální a numerický odhad únosnosti zářezu v nosnících z konstrukčního dřeva v obecném místě pomocí LEFM</a><br>

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2023

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název statě ve sborníku

WCTE 2023. Proceedings from the 13th World conference on timber engineering

ISBN

9781713873273

ISSN

—

e-ISSN

—

Počet stran výsledku

7

Strana od-do

787-793

Název nakladatele

Curran Associates

Místo vydání

Red Hook (NY)

Místo konání akce

Oslo

Datum konání akce

19. 6. 2023

Typ akce podle státní příslušnosti

WRD - Celosvětová akce

Kód UT WoS článku

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