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The sediment transport parameters and options are set using the Modify button, the forms for which forms are shown in Sediment Transport Options to Sediment Transport Options.
  The user also has the further option for setting the sediment bed with EE's Sediment Bed Initialization Tools. These are described in detail in the ViewPlan discussion.

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The number of columns shown in the input parameter grid varies with the number of classes to be modeled. The Diameter setting located at the bottom of the parameter grid sets the grain size that will be used in calculating d50's for the sediment bed. It is not used for any other calculations.

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Sediment Transport Options shows the form with the Non-Cohesives Suspended tab shown. It is similar in function and operation to the Cohesives tab. Grain size for each non-cohesive class is required for the sediment transport computations. This value is also used as the grain size for the d50 calculations. A number of options for computing equilibrium concentrations are available in the Equilibrium Conc frame. This includes the option of equilibrium concentrations calculated from Sedflume data with or without critical shear stress. Setting the settling velocity or the critical shear stress values to numbers <0 results in EFDC computing those parameters values using the Van Rijn equations (1984a, 1984b).
Pressing F2 for help pops up information relevant to the current input field.

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Sediment Transport Options shows the tab for the Non-Cohesives Bedload. The use of the Gamma parameters varies slightly between the different EFDC codes. The user should know how the Gamma's are used by reviewing the code prior to finalizing the desired inputs.

Pressing the Initialize Constants button will bring up a dialog box asking the user to select the bedload approach to use. EFDC_Explorer sets the bed load transport constants to standard literature values for the computational approach selected. The user should know how the Gamma's are used by reviewing the code prior to finalizing the desired inputs.

The Bedload Phi Options frame allows the user to choose from the following options Constant/Manual, Van Rijn, Engelund-Hansen, and Wu, Wang & Jia.

The Cell Face Transport Rate Option allows calculation based on the following options: Downwind Projection; Downwind Projection with Corner Correction; and by Averaging Vector Components. The Maximum Allowable Adverse Slope for Bedload setting will prevent bedload movement if cell to cell slope is > BLBSNT when BLBSNT is > 0.

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Sediment Transport Options shows the tab for the Morphology & Consolidation of the sediment properties option. In this tab the user may specify various bed consolidation and bed morphology settings.
The Bed Morphology Options form allows the user to choose between no bed changes (option 0) and allowing bed elevation changes (option 1). The Max. Water Depth is the maximum allowable depth to allow for the "lost" due to "NEG DEPTH" morphological change (EFDC_DSI EFDCPlus version only).

Bed Consolidation & Mechanics Options frame provides input to the main sediment bed consolidation options. The Bed Mechanics option must be 0-None, 1-Simple, or 2-Finite Strain. Option 2 is very a specialized approach and requires a detailed understanding of the of the Finite Strain implementation in the FORTRAN code. The consolidation rate is in seconds, not 1/seconds as earlier versions of EFDC.INP reported. The rate will usually be >100,000 seconds. The impact of the rate of consolidation can easily be tested using EFDC_Explorer's Single Column Sediment Layers post-processing function (see Sediment Bed Process Tools).

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The user options for the Bed processes tab are shown in Sediment Transport Options. EFDC_Explorer now employs bed armoring functionality, allowing the user the options of: No No Armoring; Non-Cohesive Armoring for Garcia-Parker; and Armoring with Active Parent Layering. The layer options frame is displayed based on which armoring option is selected. For the case of armoring with Active-Parent layering, the user needs to specify an active layer thickness, usually <5 cm but based on the d50's, and whether the active layer is controlled by mass or thickness. EFDC can optionally initialize the active layer using the initial condition bed layering. This is a good approach for initial setup of a model when the bed configuration is not well defined.

The user may also specify the Non-Cohesive Resuspension Options, with a choice of modifications based on coefficients input by the user. This option modifies the critical shear stress for resuspension (i.e TAUR) based on the fraction of cohesives.

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Sediment Transport Options shows the sediment parameters form with the Initial Conditions tab selected. On this form the user selects how they would like to initialize the bed sediments for the model. This is done by selecting the option from the Sediment Initial Conditions Options frame. These options include: Constant Water Column and Bed; Spatially Varying Water Column; Spatially Varying Bed Conditions; and Spatially Varying Bed and Water Column.

If the user elects to set the Bed Mass Specification Option to specify the mass fraction, then and the BEDLAY.INP will required as an additional IC file.

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