Tree stability under wind: simulating uprooting with root breakage using a finite element method

Area of Science:

• Forestry science
• Biomechanical engineering
• Computational modeling

Background:

• Windstorms pose a significant threat to European forests, causing substantial timber losses.
• Existing models for tree anchorage strength are limited in accurately estimating resistance during uprooting events.

Purpose of the Study:

• To develop a novel model for root anchorage strength that incorporates the successive breakage of individual roots.
• To enhance the prediction of tree stability against wind-induced forces.

Main Methods:

• Utilized the finite element method (FEM) and ABAQUS software for mechanical modeling.
• Incorporated a root failure law and the Mohr-Coulomb criterion for soil plasticity.
• Simulated tree-pulling experiments on maritime pine (Pinus pinaster) using digitized root architecture.

Main Results:

• Numerical simulations accurately reproduced successive root breakages observed during uprooting.
• The model successfully estimated anchorage strength, correlating well with in situ measurements.
• Visual localization of broken roots was possible at any simulation stage.

Conclusions:

• This research presents the first model for maritime pine anchorage strength based on individual root mechanical properties.
• The developed model's generic nature allows for adaptation to diverse tree species and soil conditions.
• The findings contribute to improved forest management and risk assessment strategies for wind disturbances.