The structure-mechanical relationship of palm vascular tissue.
The structure-mechanical relationship of palm sheath is studied with numerical and experimental methods. The cellular structure of the vascular tissue is rebuilt with an image-based reconstruction method and used to create finite element models. The validity of the models is firstly verified with the results from the tensile tests. Then, the cell walls inside each of the specific regions (fiber cap, vessel, xylem, etc.) are randomly removed to obtain virtually imperfect structures. By comparing the magnitudes of performance degradation in the different imperfect structures, the influences of each region on the overall mechanical performances of the vascular tissue are discussed. The longitudinal stiffness and yield strength are sensitive to the defects in the vessel regions. While in the transverse directions (including the radial and tangential directions), the parenchymatous tissue determines the mechanical properties of the vascular tissue. Moreover, the hydraulic, dynamic response and energy absorption behavior of the vascular tissue are numerically explored. The flexibility of natural palm tissue enhances its impact resistance. Under the quasi-static compression, the cell walls connecting the fiber cap and the vessel dissipate more energy. The dominant role of the fiber cap in the plastic energy dissipation under high-speed impact is observed. And the radially-arranged fiber cap also allows the palm tissue to improve its tangential mechanical performances under hydraulic pressure.
School of Mechanical and Automotive Engineering, South China University of Technology, 510640 Guangzhou, China.
Ningling
N
Wang
School of Mechanical and Automotive Engineering, South China University of Technology, 510640 Guangzhou, China. Electronic address: lucyliuwy@163.com.
Wangyu
W
Liu
School of Mechanical and Automotive Engineering, South China University of Technology, 510640 Guangzhou, China.
Jiale
J
Huang
School of Electronic and Information Engineering, South China University of Technology, 510640 Guangzhou, China.
Ke
K
Ma
D028023:Arecaceae / Q000502:physiology* / Q000648:ultrastructure*; D003198:Computer Simulation; D055119:Elastic Modulus / Q000502:physiology; D004735:Energy Transfer / Q000502:physiology*; D006244:Hardness / Q000502:physiology; D008954:Models, Biological; D058526:Plant Vascular Bundle / Q000502:physiology* / Q000648:ultrastructure*; D013329:Structure-Activity Relationship; D013718:Tensile Strength / Q000502:physiology; D014783:Viscosity
Cellular materials; Energy absorption; Finite element method; Mechanical characterization; Vascular bundle