Wind load estimation on an open-grown European oak tree

Nikolas Angelou*, Ebba Dellwik, Jakob Mann

*Corresponding author for this work

Research output: Contribution to journalJournal articleResearchpeer-review

Abstract

In this study, we investigate the relationship between the mean wind-induced load on an open-grown oak tree and the mean wind speed. The estimation of the wind load is based on bending moment observations on the stem, using strain gauges installed close to the base of the tree. The measurement campaign included periods where the crown was both with and without foliage. A new post-processing method to compensate for time- and temperature-dependent drifts of long-term strain gauge measurements is presented. The time-scale, at which the method is applied, is determined from the observed high coherence between the wind speed and the induced bending moments. The analysis shows that the wind load on the tree is proportional to the wind speed raised to an exponent of 1.60–1.68 and 1.90–2.01 in the case of a crown with and without leaves, respectively. The results indicate that the presence of foliage increases the wind-induced load by a factor of 2–3. The impact of the wind speed range on these results is discussed and compared to the measured wind deficit in the lee of the tree. The application of this method can potentially be extended to other tree mounted sensors.
Original languageEnglish
Article numbercpz026
JournalForestry
Volume92
Issue number4
Pages (from-to)381-392
Number of pages12
ISSN0015-752X
DOIs
Publication statusPublished - 2019

Cite this

@article{e3318da0d34a48dea9e1a01869b5f312,
title = "Wind load estimation on an open-grown European oak tree",
abstract = "In this study, we investigate the relationship between the mean wind-induced load on an open-grown oak tree and the mean wind speed. The estimation of the wind load is based on bending moment observations on the stem, using strain gauges installed close to the base of the tree. The measurement campaign included periods where the crown was both with and without foliage. A new post-processing method to compensate for time- and temperature-dependent drifts of long-term strain gauge measurements is presented. The time-scale, at which the method is applied, is determined from the observed high coherence between the wind speed and the induced bending moments. The analysis shows that the wind load on the tree is proportional to the wind speed raised to an exponent of 1.60–1.68 and 1.90–2.01 in the case of a crown with and without leaves, respectively. The results indicate that the presence of foliage increases the wind-induced load by a factor of 2–3. The impact of the wind speed range on these results is discussed and compared to the measured wind deficit in the lee of the tree. The application of this method can potentially be extended to other tree mounted sensors.",
author = "Nikolas Angelou and Ebba Dellwik and Jakob Mann",
year = "2019",
doi = "10.1093/forestry/cpz026",
language = "English",
volume = "92",
pages = "381--392",
journal = "Forestry",
issn = "0015-752X",
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}

Wind load estimation on an open-grown European oak tree. / Angelou, Nikolas; Dellwik, Ebba; Mann, Jakob.

In: Forestry, Vol. 92, No. 4, cpz026, 2019, p. 381-392.

Research output: Contribution to journalJournal articleResearchpeer-review

TY - JOUR

T1 - Wind load estimation on an open-grown European oak tree

AU - Angelou, Nikolas

AU - Dellwik, Ebba

AU - Mann, Jakob

PY - 2019

Y1 - 2019

N2 - In this study, we investigate the relationship between the mean wind-induced load on an open-grown oak tree and the mean wind speed. The estimation of the wind load is based on bending moment observations on the stem, using strain gauges installed close to the base of the tree. The measurement campaign included periods where the crown was both with and without foliage. A new post-processing method to compensate for time- and temperature-dependent drifts of long-term strain gauge measurements is presented. The time-scale, at which the method is applied, is determined from the observed high coherence between the wind speed and the induced bending moments. The analysis shows that the wind load on the tree is proportional to the wind speed raised to an exponent of 1.60–1.68 and 1.90–2.01 in the case of a crown with and without leaves, respectively. The results indicate that the presence of foliage increases the wind-induced load by a factor of 2–3. The impact of the wind speed range on these results is discussed and compared to the measured wind deficit in the lee of the tree. The application of this method can potentially be extended to other tree mounted sensors.

AB - In this study, we investigate the relationship between the mean wind-induced load on an open-grown oak tree and the mean wind speed. The estimation of the wind load is based on bending moment observations on the stem, using strain gauges installed close to the base of the tree. The measurement campaign included periods where the crown was both with and without foliage. A new post-processing method to compensate for time- and temperature-dependent drifts of long-term strain gauge measurements is presented. The time-scale, at which the method is applied, is determined from the observed high coherence between the wind speed and the induced bending moments. The analysis shows that the wind load on the tree is proportional to the wind speed raised to an exponent of 1.60–1.68 and 1.90–2.01 in the case of a crown with and without leaves, respectively. The results indicate that the presence of foliage increases the wind-induced load by a factor of 2–3. The impact of the wind speed range on these results is discussed and compared to the measured wind deficit in the lee of the tree. The application of this method can potentially be extended to other tree mounted sensors.

U2 - 10.1093/forestry/cpz026

DO - 10.1093/forestry/cpz026

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SP - 381

EP - 392

JO - Forestry

JF - Forestry

SN - 0015-752X

IS - 4

M1 - cpz026

ER -