Nonlinear dynamics and failure wind velocity analysis of urban trees

- Journal title : Wind and Structures
- Volume 22, Issue 1, 2016, pp.89-106
- Publisher : Techno-Press
- DOI : 10.12989/was.2016.22.1.089

Title & Authors

Nonlinear dynamics and failure wind velocity analysis of urban trees

Ai, Xiaoqiu; Cheng, Yingyao; Peng, Yongbo;

Ai, Xiaoqiu; Cheng, Yingyao; Peng, Yongbo;

Abstract

With an aim to assess the wind damage to urban trees in more realistic conditions, the nonlinear dynamics of structured trees subjected to strong winds with different levels is investigated in the present paper. For the logical treatment of dynamical behavior of trees, material nonlinearities of green wood associated with tree biomechanics and geometric nonlinearity of tree configuration are included. Applying simulated fluctuating wind velocity to the numerical model, the dynamical behavior of the structured tree is explored. A comparative study against the linear dynamics analysis usually involved in the previous researches is carried out. The failure wind velocity of urban trees is then defined, whereby the failure percentages of the tree components are exposed. Numerical investigations reveal that the nonlinear dynamics analysis of urban trees results in a more accurate solution of wind-induced response than the classical linear dynamics analysis, where the nonlinear effect of the tree behavior gives rise to be strengthened as increasing of the levels of wind velocity, i.e., the amplitude of 10-min mean wind velocity. The study of relationship between the failure percentage and the failure wind velocity provides a new perspective towards the vulnerability assessment of urban trees likely to fail due to wind actions, which is potential to link with the practical engineering.

Keywords

nonlinear dynamics;failure wind velocity;urban trees;geometric nonlinearity;tree biomechanics;wind damage;

Language

English

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