Finite element analysis of structural safety and support reinforcement efficacy in a large old Zelkova tree: A case study of a natural monument

The structural safety of a natural monument tree was evaluated using the finite element method (FEM), assuming the tree’s material properties to be isotropic. This research involved quantifying external forces, gravity, snow, and wind loads, and analyzing the resulting stress and displacement of the tree. The effectiveness of support structures in improving the tree’s overall structural stability was also investigated. The results show that the greatest displacement and stress occur under snow load conditions. The highest stress was observed in branch D (13.63 MPa) under snow load without any support structure. When this stress was compared with the bending strength of the Zelkova tree’s branches (69.7 MPa), it was found that the tree has a safety margin of 56.1 MPa. Furthermore, when the current support structure positions were considered, branch F, which is supported, exhibited a significant reduction in displacement (by 30% to 42%) and stress (by 84% to 92%) compared to conditions without support. Conversely, branch D, which lacks a support structure, showed no reduction in displacement or stress. These results show that FEM simulation can contribute to the review of reinforcement facility installation to ensure the stability of large old trees.