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Failure mechanism of hollow tree trunks due to cross-sectional flattening.

ABSTRACT: Failure of hollow trees in urban areas is a worldwide concern, and it can be caused by different mechanisms, i.e. bending stresses or flattening-related failures. Here we derive a new analytical expression for predicting the bending moment for tangential cracking, and compare the breaking moment of various failure modes, including Brazier buckling, tangential cracking, shear failure and conventional bending failure, as a function of t/R ratio, where t and R are the trunk wall thickness and trunk radius, respectively, of a hollow tree. We use Taiwan red cypress as an example and show that its failure modes and the corresponding t/R ratios are: Brazier buckling (Mode I), tangential cracking followed by longitudinal splitting (Mode II) and conventional bending failure (Mode III) for 0?

SUBMITTER: Huang YS

PROVIDER: S-EPMC5414253 | biostudies-literature | 2017 Apr

REPOSITORIES: biostudies-literature

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Failure mechanism of hollow tree trunks due to cross-sectional flattening.

Huang Yan-San YS Hsu Fu-Lan FL Lee Chin-Mei CM Juang Jia-Yang JY

Royal Society open science 20170412 4

Failure of hollow trees in urban areas is a worldwide concern, and it can be caused by different mechanisms, i.e. bending stresses or flattening-related failures. Here we derive a new analytical expression for predicting the bending moment for tangential cracking, and compare the breaking moment of various failure modes, including Brazier buckling, tangential cracking, shear failure and conventional bending failure, as a function of t/R ratio, where t and R are the tr ...[more]

PMID: 28484616

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