Strain analysis of fruit tree branch under large deflection considering flexural deformation characteristics

摘要

© 2022 The Japan Society of Mechanical Engineers. All Rights Reserved.Fruit tree branches are deflected with large deformation under bending loads applied owing to fruit weight and environmental burdens such as wind and snow. Stress and strain analyses in large bending deformations of tree branches can prevent tree failure. An extensive deformation analysis method for a fruit tree branch subjected to fruit weight applied as concentrated and distributed type loads is proposed herein. The method is based on actual loading tests for identifying the material properties of an apple tree branch and numerical simulation for deformation analysis. The estimated branch geometry at significant bending is obtained via iterative calculations and is consistent with the actual loading case; hence, it identifies the local bending stiffness. The effects of both the base angles of a cantilever-modeled tree branch with different bending stiffness distributions and initial curvatures and the load distribution patterns simulating the fruit arrangement on the branch on the maximum bending strain are investigated via numerical deformation analysis. The method provides critical loading conditions for fruit cultivation, focusing on the maximum strain on the branch. The information gained can be applied for generating fruit cultivation plans, where reduction in load applied on the fruit branch is emphasized.