Author(s): Li Chen; Mark C. Stone; Kumud Acharya; Kent A. Steinhaus
Keywords: Drag force; ecohydraulics; hydraulic roughness; stress; vegetation bending
Abstract: Vegetation plays an important role in stream processes and management efforts. However, the description of mechanical behaviours of vegetation–fluid interaction requires an improved understanding of the underlying physics and of the methods used for investigating this interaction. The objective of this research was to develop a method for describing vegetation mechanics in flowing fluids. This was accomplished by outlining methods for describing vegetation responses to flow under rigid and bending conditions for simple vegetation elements. The results of the theoretical analyses provide insight into influences of vegetation biomechanical properties to force distributions, bending behaviour, and potential vegetation rupture locations and conditions. The approach can be used to estimate hydraulic conditions for vegetation failure and flow resistance caused by vegetation, especially for flexible species. Although the techniques developed here are based on simplifying assumptions, the present analysis provides a foundation for future development for submerged vegetation and complex vegetation clusters.