基于流固耦合分析支撑架对云杉抗风性的影响.

Under strong winds, newly transplanted trees can tilt or fall, causing economic losses and injuries. Therefore, studying the wind resistance of trees and methods to enhance their wind resistance is of great significance. In this study, 3D simplified models of spruce were built before and after the installation of support frames in them. The trees were 8 m in height, 4 m in crown diameter, with a trunk diameter of 0.3 m at the base. Corresponding mechanical properties were assigned to the models and fluid-solid interaction was numerically simulated. The results showed that without support, the displacement of the spruce treetop, shear stress on branches, and bending moment at the base increased with increasing wind speed. At a wind speed of 20 m.s-1, the maximum shear stress in the transverse direction of spruce was 2.6 MPa, exceeding 85% of its transverse shear strength. This indicates that there is a possibility of shear failure in the tree with the failure point at the junction of the primary branch and the main stem. Supporting the tree at 1/8, 2/8, and 3/8 of its height reduced the displacement of the treetop, shear stress on branches, and bending moment at the base, ultimately lowering the risk of shear failure and falling. When the support frame was placed at 2/8 of the tree's height, the shear stress on the tree was minimized, reducing the risk of branch breakage by 50%. However, the part of the tree above the support frame had an increased wind-induced oscillation frequency compared to the unsupported tree, reducing the tree's stability and increasing the risk of branch breakage owing to prolonged high-frequency vibration. Numerical simulation of wind-induced tree response is highly customizable, and its results have reference value for studying wind resistance of trees and designing support frames for trees. [ABSTRACT FROM AUTHOR]