[1]艾晓秋,彭勇波,承颖瑶.城市行道树动力学特性与风致破坏分析[J].自然灾害学报,2018,(01):027-32.[doi:10.13577/j.jnd.2018.0104]
 AI Xiaoqiu,PENG Yongbo,CHENG Yingyao.Wind-induced failure and dynamical behaviors of urban trees[J].,2018,(01):027-32.[doi:10.13577/j.jnd.2018.0104]
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城市行道树动力学特性与风致破坏分析
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《自然灾害学报》[ISSN:/CN:23-1324/X]

卷:
期数:
2018年01期
页码:
027-32
栏目:
出版日期:
2018-02-28

文章信息/Info

Title:
Wind-induced failure and dynamical behaviors of urban trees
作者:
艾晓秋1 彭勇波12 承颖瑶1
1. 同济大学 上海防灾救灾研究所, 上海 200092;
2. 同济大学 土木工程防灾国家重点实验室, 上海 200092
Author(s):
AI Xiaoqiu1 PENG Yongbo12 CHENG Yingyao1
1. Shanghai Institute of Disaster Prevention and Relief, Tongji University, Shanghai 200092, China;
2. State Key Laboratory of Disaster Reduction in Civil Engineering, Tongji University, Shanghai 200092, China
关键词:
行道树失效风速有限元频域分析材料强度树木形态
Keywords:
urban treefailure wind velocityfinite elementfrequency analysismaterial strengthtree configuration
分类号:
O242;TB123;X43
DOI:
10.13577/j.jnd.2018.0104
摘要:
建立了考虑树木形态和分枝影响的行道树风灾破坏评估有限元模型,采用频域分析方法对行道树的失效风速进行了研究。以特定参数的行道树为研究对象,得到对工程实际具有借鉴意义的结论:行道树的模态频率集中于3个较为集中的范围,分别对应于结构主干、一级小枝和二级小枝;树木的风致破坏是各因素(风力、树木材料强度等)综合影响的结果:行道树破坏的可能性随着平均风速的增大而增大,随着树木材料强度的增大而减小;行道树各部分的失效风速存在明显差异,随着风速的增加,枝条失效先于主干失效,而二级小枝的损失率要大于一级小枝。数值分析表明,本文提出的方法能考虑树木空间形态对风致破坏的影响,比不考虑分枝的一般简化方法更能合理地评估行道树的失效风速。
Abstract:
In this paper, an investigation of wind damage to urban trees using the frequency scheme is carried out. In order to accurately model the conformation of the tree, the finite element method considering tree configuration and branches is employed. For illustrative purposes, an urban tree with specified structural parameters is investigated. It is found that modal frequencies are distributed in a relatively concentrated range, which can be divided into three groups corresponding to the modal frequencies of the trunk, primary branches and secondary branches, respectively. Numerical analysis indicates that the tree failures result from the coupled effects of multiple factors, such as the wind velocity and material strength of the green wood. An increase, moreover, in wind velocity enlarges the failure probability of the tree, but an increase in material stress reduces the failure probability. It is also shown that the failure wind velocity corresponding to the components of tree varies significantly; the branches failure occurs earlier than the trunk failure while the secondary branches are more likely to fail than the primary branches along with the increase of mean wind velocity. The proposed new scheme has the advantage over the general simplified methods without consideration of branches that the failure wind velocity can be rationally evaluated through accommodating the influence of structural topology.

参考文献/References:

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备注/Memo

备注/Memo:
收稿日期:2016-12-29;改回日期:2017-12-29。
基金项目:国家重点研发计划(2017YFC0803300)
作者简介:艾晓秋(1977-),女,助理研究员,博士,主要从事城市灾害防御研究.E-mail:aixiaoqiu@tongji.edu.cn
通讯作者:彭勇波(1978-),男,副研究员,博士,主要从事工程结构灾变动力学与性态控制研究.E-mail:pengyongbo@tongji.edu.cn
更新日期/Last Update: 1900-01-01