Grade Stabilization Structures

Grade Stabilization Structures
-Enhancing environmental quality by developing alternatives for erosion control

Grade stabilization structures such as rock chutes, canopy hood inlets, and low drop structures are installed to convey water from a field to a lower elevation such as a drainage ditch, waterway, or outlet channel. USDA-ARS Hydraulic Engineering Research Unit (HERU) scientists have developed a variety of standards through the years to address areas of erosional concern such as gullies, headcuts, and streambank stabilization. Special attention to some of these structures have been given to maintain or improving habitat and wildlife when applicable. Geometrically scaled models to accurately simulate prototype flow conditions allow scientists to optimize the efficiency and design of the hydraulic structure. Model studies are intended to provide safe, economical design alternatives for practicing engineers. Here at the HERU, scientists can conduct research on small-scale to prototype dimensions. With an open-air laboratory environment with nearly 100 acres of land available for research expansion, scientists can conduct research at prototype dimensions if necessary. Scientists are also equipped with indoor modelling facilities to conduct small-scale testing. Model flow rates from a trickle up to 120 cfs of gravity flow is available for research. Physical scale modeling is a reliable method for reproducing results at prototype scale when the modeling is performed properly. Physical modeling may be used to optimize the design of hydraulic structures through the examination of small changes (i.e. geometry, flow conditions) in the design. In addition, physical modeling may unveil issues (i.e. vortices, cavitation, scour development, etc.) related to the hydraulic performance of the structure. HERU scientists have partnered with federal government agencies (i.e. USDA-Natural Resources Conservation Service (NRCS), U.S. Bureau of Reclamation, and U.S. Army Corps of Engineers); state, county, and local agencies (i.e. Gwinnett County, Georgia); and academia (i.e. Oklahoma State University, Kansas State University, Baylor University, University of Mississippi, among others) to address specific concerns as they relate to hydraulic engineering, geotechnical engineering, and computational fluid dynamics. Design standards for grade stabilization structures such as rock chutes, low drop structures, and canopy hood inlets have been adopted by the USDA-NRCS and incorporated into their National Engineering Handbook as well as in several of their conservation practice standards. Examples of grade stabilization structure research conducted by HERU scientists include:

Canopy Hood inlets

Low drop structures

Rock Chutes