Using stationing to locate measures
Stationing is the fundamental system of measurement used for road pipeline layout and construction. Stations are reference points that are placed along the horizontal measurement of a route centerline or a baseline at some regular interval. Generally, the distance between two adjoining stations along a route is 100 feet. The first station located at the beginning of the baseline is 0+00, and the next station located 100 feet from it is 1+00. Therefore, a station number of 10+34.05 denotes 1,034.05 feet (10*100 + 34.05) from the starting station.
The station numbers increase from west to east or south to north based on the cardinal direction of the overall pipeline. For pipeline projects, a starting reference station is first established, and then all distances along the route centerline are measured from that point location. You can add event data to routes by entering station numbers in the Line Events tool interface. The station data is translated to routes and measures for storage.
You can use the stationing data as an input for adding linear events by using these three scenarios:
- Create a starting or base station on the route and enter the station values as an offset from that station.
- Identify a starting or base station on the route and enter the station values as an offset from that location.
- Use the preexisting stations on the route to calculate or enter the measures in the form of station values.
Locating measures by creating a starting or base station on the route
You can use this method when no stations are present on the route. You'll create a starting or base station on the route and specify the stationing values for measures. The measures will be located at an offset from the starting station. As shown in the example below, a starting station (yellow star) is temporarily located and a station value is provided. The event's start or end location is then identified by using an offset distance (in station values) from the starting station. When the new linear events are created using this method, the stationing data is translated to routes and measures for storage.
- Open a web browser and browse to the Event Editor.
- Click the Edit tab.
- In the Edit Events group, click the Line Events button .
- Click the Network (LRM) drop-down arrow and choose the network that will serve as a source LRM for defining the input measures for the new linear events.
The Network (LRM) is an LRS Network published as a layer in the Event Editor (EE). You can specify the LRS Network to be used as the LRM for defining the start and end measures of the new linear event. Event Editor (EE) also accepts measures in a network or LRM other than the one with which the linear event layer is associated.
The new event will be associated with the routes (route IDs) from the LRS Network with which the event location intersects.
- Type the name of the line feature on which the events will be located in the Line Name text box.
Click the Select a Line on the Map tool and choose the line from the map.
If the selected line is not in the active view of the map, click the Zoom to the line on the map button to refresh the map display to zoom in to the entire extent of the selected line.
The line is highlighted in light blue. The arrow at the end shows the direction of calibration of the line.
- In the From section, click the Method drop-down arrow and choose Starting station and offset.
The Starting Station section appears.
- In the Starting Station section, for Station, click the Select a Location on the Map tool and select the location of the starting station on a route in the map.
The location of the starting station can also be found by inserting a DGN or a DWG file containing the survey information or engineering drawing into the map. Go to the Map tab, and in the Contents group, click the Add Data button. For more information, see Adding DGN or DWG data.
- A yellow star shows the location of the starting station on a route in the map.
- The LRM measure equivalent of the location is displayed in the Location field. For example, if the LRM is milepoint, the number of miles at that location will be displayed.
- The Route Name text box is populated in the From section.
- Type the station value of the starting station in terms of station values.
- Click the drop-down arrow and choose the units for station values.
- Click the Direction drop-down arrow and choose the direction.
This selection indicates the direction the station values increase along the route compared to the direction of calibration of the route.
- In the From section, provide the Station number using any one of these options to allot the From Measure for the event:
- Click the Select a Location on the Map tool , and click a location on the selected route. The station number is derived from the route.
- Type the station number.
The From Measure location will be placed at an offset from the starting station.
A green cross symbol appears at the selected location on the map.
- You can use separate methods to locate the From and To measures of the events. Therefore, in the following example, the To Measure of the event is located by using an intersection offset.
A red cross symbol appears at the selected location on the map.
- Choose the date that will define the start date of the events.
- Click the Start Date drop-down arrow to choose the start date using a calendar.
- Check the Use route start date check box to use the start date of the routes.
The start date defaults to today's date, but you can choose a different date using the date picker. The end date is optional, and if it's not provided, the event remains valid now and into the future.
- Choose the date that will define the end date of the events.
- Click the End Date drop-down arrow to choose the end date using a calendar.
- Check the Use route end date check box to use the end date of the routes.
- You can choose three different data validation options to prevent erroneous input while characterizing a route with linear events.
- Retire overlaps—The system will adjust the measure and start and end dates of existing events in such a way that the new event does not cause an overlap with respect to time and measure values.
- Merge coincident events—When all attribute values for a new event are exactly the same as an existing event, and if the new event is adjacent to or overlapping the existing event in terms of measure values, the new event is merged into the existing event, and the measure range is expanded accordingly.
- Prevent measures not on route—This data validation option ensures that the input measure values for the From Measure and To Measure values fall within the minimum and maximum range of measure values on the selected route.
- Click Next.
The tab showing the attribute set for the events opens. The event fields are shown under the attribute group named Edits.
Note:You can use the check boxes to add data for specific events within the attribute set. No records are added for unchecked events.
- Provide the attribute information for the new event in the tables defined by attribute sets.
You can use the Copy Attributes tool to copy event attributes from another route. Click the tool and click a route on the map to copy the event attributes.
Event Editor (EE) uses a default attribute set, as seen on the Edit tab. You can modify the attribute set to create custom attribute sets or use the administrator-configured attribute set.
- Use these options to access more information on the attribute set.
- Check the Show network names check box to see which LRS Network the selected event layer is associated with.
- The list of attributes within the tables defined by attribute sets can be from more than one event layer. If you want to identify the source event layer for each attribute, check the Show layer names check box.
- Checking the Go to the next measure upon save check box results in prepopulating the From Measure value using the To Measure value of the present section to continue the event creation process.
- Click Save.
The new linear events are created and displayed on the map.
After a linear event has been successfully created, you have the following two options to continue characterizing the route:
- If you click New Edit, all the input entries in the form are cleared, and the default values from the geodatabase are populated in the table.
- If you click Next Edit, all the existing entries in the form and the attribute set are retained for convenience and for quick editing of similar characteristics.