Extract Weir Crest Geometry Command

The Extract Weir Crest Geometry command allows the software to utilize AutoCAD Civil 3D surfaces, contours, TINs, DTMs, DEMs, survey points, and other external digital elevation terrain data to extract weir crest geometry for the following structure types:

• Lateral structures
• Inline structures
• SA/2D connections

This article describes how to use the Extract Weir Crest Geometry command in GeoHECRAS.

Extracting Weir Crest Geometry for Lateral Structures

The Extract Weir Crest Geometry command allows the user to extract the weir crest geometry for the selected lateral structure using the specified terrain elevation data sources.

Follow the steps below to use the Extract Weir Crest Geometry command:

1. From the Input ribbon menu, click the Lateral Structures dropdown menu and select the Extract Weir Crest Geometry command.
   
2. The Extract Weir Crest Geometry dialog box will be displayed.
   

The following sections describe how to interact with the Extract Weir Crest Geometry dialog box.

Selecting Lateral Structure

The Select Lateral Structure section allows the user to select the lateral structure for which the weir crest geometry will be extracted. In this section, the user can select the river, reach, and the lateral structure river station from the corresponding dropdown combo boxes. Alternatively, the user can click the [Pick] button to select the lateral structure from the Map View.

Extraction Options

This section allows the user to control which portions of the cross sections should be extracted. The following options are available:

• Trim overlapping cross sections
  This checkbox option is used to automatically trim the extended cross sections to the lateral structure. By default, this checkbox is unchecked.

• Extend shortened cross sections
  This checkbox option is used to automatically extend the shortened cross sections to the lateral structure. By default, this checkbox is unchecked.

Refer to this article in our knowledge base to learn more about trimming and extending cross sections.

Extract Elevation Data

This section allows the user to define the elevation data source(s) to be used for extracting the weir crest geometry.

The Primary Elevation Data and Secondary Elevation Data panels are used to define the primary and secondary (if available in the project) elevation data sources for extracting weir crest geometry. Depending on the selected elevation data source type, the content of these panels changes to specify additional elevation data information.

Refer to this article in our knowledge base for information on the types of terrain elevation data that can be used to extract weir crest geometry.

When a secondary elevation data source is available, the software forms a concave hull around the primary elevation data source. For locations where elevation data from the primary data source are unavailable, the software will use the elevation data from the secondary data source.

Note that the user cannot utilize the same data source for defining the primary and secondary elevation data.

The user can click the [Swap Sources] button to swap the selected elevation source from primary elevation data to secondary elevation data and vice versa.

Once all the options have been defined, click the [OK] button. The software will then extract the weir crest geometry for the selected lateral structure.

Extracting Weir Crest Geometry for Inline Structures

The Extract Weir Crest Geometry command allows the user to extract the weir crest geometry for the selected inline structure using the specified terrain elevation data sources.

Follow the steps below to use the Extract Weir Crest Geometry command:

1. From the Input ribbon menu, click the Inline Structures dropdown menu and select the Extract Weir Crest Geometry command.
   
2. The Extract Weir Crest Geometry dialog box will be displayed.
   

The following sections describe how to interact with the Extract Weir Crest Geometry dialog box.

Selecting Inline Structure

The Select Inline Structure section allows the user to select the inline structure for which the weir crest geometry will be extracted. In this section, the user can select the river, reach, and inline structure river station from the corresponding dropdown combo boxes. Alternatively, the user can click the [Pick] button to select the inline structure from the Map View.

Extract Elevation Data

This section is similar to the Extract Elevation Data section explained above for the lateral structures.

Once all the options have been defined, click the [OK] button. The software will then extract the weir crest geometry for the selected inline structure.

Extracting Weir Crest Geometry for SA/2D Connections

The Extract Weir Crest Geometry command allows the user to extract weir crest geometry for the selected SA/2D connection using the specified terrain elevation data sources.

Follow the steps below to use the Extract Weir Crest Geometry command:

1. From the Input ribbon menu, click the SA/2D Connections dropdown menu and select the Extract Weir Crest Geometry command.
   
2. The Extract Weir Crest Geometry dialog box will be displayed.
   

The following sections describe how to interact with the Extract Weir Crest Geometry dialog box.

Selecting SA/2D Connection Weir Polyline

The Select SA/2D Connection Weir Polyline section allows the user to select the SA/2D connection weir centerline for which the weir crest geometry will be extracted.

Follow the steps below to select the SA/2D connection weir centerline:

1. Click the [Pick] button, and the dialog box will temporarily disappear.
   
2. The status bar will prompt the user to select the SA/2D connection weir centerline from the Map View. Click on the previously drawn SA/2D connection weir centerline on the Map View to select it.
3. Upon clicking the SA/2D connection weir centerline, the Extract Weir Crest Geometry dialog box will be redisplayed, and the status of the Structure centerline read-only field will be changed from Not Selected to Selected.
   

Extract Elevation Data

This section is similar to the Extract Elevation Data section explained above for the lateral structure.

Once all the options have been defined, click the [OK] button. The software will then extract the weir crest geometry for the selected SA/2D connection.