2.0

Calculating Culvert Size and Shape
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2 Do one of the following to one of the three available control options:
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Select Inlet to calculate the culvert design for inlet control.For more
information, see the following section, Specifying the Inlet Control Type.
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Select Outlet to calculate the culvert design for outlet control.
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Select Optimum to let the program determine which control is optimum for
calculating the culvert design.
3 Under Outlet Control, type a coefficient in the Entrance Loss box.
You can also click Select to select a coefficient from the Culvert Entrance Loss
Values dialog box. This dialog box describes entrance conditions for the culvert
and associated entrance loss coefficients.
4 Under Flowrate Range, type a minimum flow rate, maximum flow rate, and a
flow increment in the Minimum Flow, Maximum Flow, and Flow Increment
boxes, respectively. These values are used when calculating the P-curve and the
Fit-Plot.
5 Under Chart And Scale, click Select to select an inlet control type from the Inlet
Control Types dialog box.
The design type determines the culverts chart type and scales. Pick the
description that most closely matches your design conditions.
6 In the Number of Barrels box, type the number of barrels for this culvert.
7 Click OK to return to the Culvert Design dialog box.
Specifying a Coefficient
The Culvert Entrance Loss Values dialog box describes entrance conditions for
the culvert and associated entrance loss coefficients.
To specify a coefficient from the dialog box
1 In the Culvert Settings dialog box, click the Select button next to the Entrance
Loss box to display the Culvert Entrance Loss Values dialog box.
2 Select a coefficient by placing your cursor in the appropriate column and
clicking anywhere in the text box that contains the value you want to use.
Use the navigation buttons on the right side of the dialog box to move through
the list of descriptions and coefficients.