An essential prerequisite for the efficient biomechanical tailoring of crops is to accurately relate mechanical behavior to compositional and morphological properties across different length scales. In this article, we develop a multiscale approach to predict macroscale stiffness and strength properties of crop stem materials from their hierarchical microstructure. We first discuss the experimental multiscale characterization based on microimaging (micro-CT, light microscopy, transmission electron microscopy) and chemical analysis, with a particular focus on oat stems. We then derive in detail a general micromechanics-based model of macroscale stiffness and strength. We specify our model for oats and validate it against a series of bending experiments that we conducted with oat stem samples. In the context of biomechanical tailoring, we demonstrate that our model can predict the effects of genetic modifications of microscale composition and morphology on macroscale mechanical properties of thale cress that is available in the literature.
Bibliographical noteFunding Information:
The authors gratefully acknowledge support from the Minnesota Department of Agriculture under Grant No. 122130, and from the National Science Foundation via the NSF Grant CISE-1565997. The first author (T. Gangwar) was partially supported by a Sommerfeld Fellowship awarded by the Department of Civil, Environmental, and Geo-Engineering and a MnDRIVE Informatics Graduate Fellowship, both at the University of Minnesota, which are gratefully acknowledged. The authors would like to express their gratitude to Young Heo and Bonita VanHeel (Minnesota Dental Research Center for Biomaterials and Biomechanics, University of Minnesota) for their help with the bending experiments. The authors also acknowledge Dimitri von Ruckert for the field management and University Imaging Centers at the University of Minnesota for transmission electron microscopy images.
- Biomechanical tailoring
- Continuum micromechanics
- Hierarchical multiscale materials