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Simulating Dredging and Sediment Feedbacks with HEC-RAS. Stanford Gibson, PhD Hydrologic Engineering Center USACE. Road Map. Importance of Sediment Feedbacks on Dredged Channels Overview of HEC-RAS Two Examples of Navigation Dredging Simulations New Dredging Capabilities in HEC-RAS 4.2.
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Simulating Dredging and Sediment Feedbacks with HEC-RAS Stanford Gibson, PhD Hydrologic Engineering Center USACE
Road Map • Importance of Sediment Feedbacks on Dredged Channels • Overview of HEC-RAS • Two Examples of Navigation Dredging Simulations • New Dredging Capabilities in HEC-RAS 4.2
Importance of Modeling Feedbacks on Sediment Systems Sediment Deposition Channel Geometry Change Dredging
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HEC-RAS Sediment Transport • Mobile Boundary Hydraulic Model • Captures Sediment-Hydraulic Feedbacks • Cohesive and Cohesionless Transport • Public Domain - 1D Model – Widely Applied • There is probably already an HEC-RAS hydraulic model of your system • Good at Depositional Sediment Modeling • Dredging Capabilities
Ontonagon River Cuyahoga River
Ontonagon River Model and Calibration by Calvin Creech of LRD
Cuyahoga River 3 things
Classic Dredging Capabilities • HEC-RAS 4.1 followed HEC 6 • Allow user definition of time and extent of dredging configuration. • left/right extent and elevation for each XS • Only rectangular dredging cuts. • Instantaneous Dredging
New Dredge Options in Version 4.2
Time Integrated Dredging
Missouri River Through Kansas City
Modeling Residual Sediment Suspension
Modeling Residual Sediment Suspension
Automated Dredging Triggers
Bed Layers z z Gradations can then be “layered” Dx Dx Dx Dx Dx Dx Resistant Reservoir Layer Lacustrian Glacial Strata Glacial Outwash Strata Erodibility=f(Density) Density=f(Depth)
Stanford Gibson: stanford.gibson@usace.army.mil HEC-RAS: www.hec.usace.army.mil Collaborators: The RAS Team: Gary Brunner, Mark Jensen, Steve Piper, Cameron Ackerman District Partners: John Shelley NWK, Calvin Creech LRD