This subassembly is used to insert a median at the centerline, with asymmetrical barriers on either side of the centerline, and a tapered bottom with an optional key.
The pavement structure follows the standards described in “Pavement Structure of Paved Sections" in the Autodesk Civil 3D Help.
Attachment
The attachment point is at the middle of the median. The median is placed on either side with appropriate components as specified by the input parameters.
Input Parameters
Note: All dimensions are in meters or feet unless otherwise noted. All slopes are in run-over-rise form (for example, 4 : 1) unless indicated as a percent slope with a “%” sign.
| Parameter | Description | Type | Default |
|---|---|---|---|
| Left Median Width | Width of the median to the left of attachment point, including barrier area | Numeric, positive |
2.0m 6.0 ft |
| Right Median Width | Width of the median to the right of attachment point, including barrier area | Numeric, positive |
2.0m 6.0 ft |
| Crown Point at Center | Specifies that attachment point will be coded as Crown | Yes/No | No |
| Left Median Cross Slope | Cross slope of the median to the left of attachment point | Numeric | 0% |
| Right Median Slope | Cross slope of the median to the right of attachment point | Numeric | 0% |
| Barrier Option | Specifies to place barriers on left and/or right sides | String: (a) None, (b) Both Sides,(c) Right (d) Left | Both Sides |
| Barrier Top Width | Width of the top of the barrier | Numeric, positive |
0.15 m 0.5 ft |
| Barrier Middle Width | Width of the middle of the barrier | Numeric, positive |
0.225 m 0.75 ft |
| Curb Height | Height of the curb at the bottom of barrier | Numeric, positive |
0.075 m 0.25 ft |
| Barrier Bottom Width | Width of the bottom of the barrier | Numeric, positive |
0.6 m 2.0 ft |
| Barrier Height | Height to the top of the barrier | Numeric, positive |
0.9 m 3.0 ft |
| Barrier Middle Height | Height to the middle of the barrier | Numeric, positive |
0.45 m 1.5 ft |
| Shoulder Height Offset | Difference in the median edge point elevation with respect to edge of paved shoulder | Numeric |
0.015 m 0.05 ft |
| Left Shoulder Width | Width from the left shoulder from inside edge of pavement to median start point. Zero value can be entered if no shoulder is needed on the left side. | Numeric, Positive |
1.2 m 4.0 ft |
| Left Shoulder Default Slope | Default cross slope of the shoulder surface. This value is used if superelevation slope is not used, or is not specified for the baseline alignment. | Numeric, Positive | -2% |
| Left Shoulder - Use Superelevation Slope | Specifies to use the slope from the superelevation specification defined on the baseline alignment |
Selection List:
|
Yes |
| Right Shoulder Width | Width from the right shoulder from inside edge of pavement to median start point. Zero value can be entered if no shoulder is needed on the right side. | Numeric, Positive |
1.2 m 4.0 ft |
| Right Shoulder Default Slope | Default cross slope of the right shoulder surface. This value is used if superelevation slope is not used, or is not specified for the baseline alignment. | Numeric, Positive | -2% |
| Right Shoulder - Use Superelevation Slope | Specifies to use the slope from the superelevation specification defined on the baseline alignment. |
Selection List:
|
Yes |
| Shoulder Slope Direction | Specifies whether the shoulder slopes away from the crown or towards the crown |
Selection List:
|
Away from Crown |
| Subbase Slope | Cross slope of subbase from each end towards middle. If optional drain key is selected, then it is to that point. | Numeric | -4% |
| Drain Key | Specifies to add drain key below one of the barriers. | String; (a) None, (b) Below Left Barrier, (c) Below Right Barrier | Below Right Barrier |
| Key Width | Width of the optional key bottom | Numeric, positive |
0.3 m 1.0 ft |
| Key Depth | Depth of the optional key on the short side | Numeric, positive |
0.3 m 1.0 ft |
| Left Pave1 Depth | Depth between finish grade and Pave1 for the left shoulder | Numeric, positive |
0.025 m 0.083 ft |
| Left Pave2 Depth | Depth second level pavement material for the left shoulder | Numeric, positive |
0.025 m 0.083ft |
| Left Base Depth | Depth of base course (between Pave2 and Base) for the left shoulder | Numeric, positive |
0.100 m 0.333 ft |
| Left Subbase Depth | Depth of the subbase layer at the left inside edge of pavement (start of the left shoulder). If shoulder width is set to zero , then this is the depth of the subbase at left end of the median. | Numeric |
0.300 m 1.0 ft |
| Left Pave2 Extension | Width that the Pave2 layer extends beyond the edge of paved shoulder on the left side into the median. This is provided even if the left shoulder width is set to zreo. | Numeric, positive |
0.1 m 0.33 ft |
| Left Base Extension | Width that the Base layer extends beyond the edge of paved shoulder on the left side into the median. This is provided even if the left shoulder width is set to zero. | Numeric, positive |
0.25 m 0.83 ft |
| Right Pave1 Depth | Depth between finish grade and Pave1 for the right shoulder | Numeric, positive |
0.025 m 0.083 ft |
| Right Pave2 Depth | Depth second level pavement material for the right shoulder | Numeric, positive |
0.025 m 0.083 ft |
| Right Base Depth | Depth of base course (between Pave2 and Base) for the right shoulder | Numeric, positive |
0.100 m 0.333 ft |
| Right Subbase Depth | Depth of the subbase layer at the right inside edge of pavement (start of the right shoulder). If shoulder width is set to zero, then this is the depth of the subbase at right end of the median. | Numeric |
0.300 m 1.0 ft |
| Right Pave2 Extension | Width that the Pave2 layer extends beyond the edge of paved shoulder on the right side into the median. This is provided even if the right shoulder width is set to zero | Numeric, positive |
0.1 m 0.33 ft |
| Right Base Extension | Width that the Base layer extends beyond the edge of paved shoulder on the right side into the median. This is provided even if the right shoulder width is set to zero. | Numeric, positive |
0.25 m 0.83 ft |
Target Parameters
This section lists the parameters in this subassembly that can be mapped to one or more target objects, such as a surface, alignment, or profile object in a drawing. For more information, see To Specify Corridor Targets.
|
Parameter |
Description |
Status |
|---|---|---|
|
Left Paved Shoulder Width |
May be used to override the fixed Shoulder Width on the left side and tie the inside edge-of-shoulder to an offset alignment. The following object types can be used as targets for specifying this offset: alignments, polylines, feature lines, or survey figures. |
Optional |
|
Right Paved Shoulder Width |
May be used to override the fixed Shoulder Width on the right side and tie the inside edge-of-shoulder to an offset alignment. The following object types can be used as targets for specifying this offset: alignments, polylines, feature lines, or survey figures. |
Optional |
Output Parameters
|
Parameter |
Description |
Type |
|---|---|---|
|
Superelevation Axis of Rotation |
Indicates whether the subassembly supports the axis of rotation calculation. To view a description of the parameter, in the Properties window, hover the cursor over the parameter. For more information, see Profile Grade Line Adjustments During Superelevation. |
Static (Description) |
|
Barrier Height |
Height to the top of the barrier. |
Numeric, positive |
|
Left Shoulder Slope |
Slope of the left paved shoulder. |
Numeric, positive |
|
Right Shoulder Slope |
Slope of the right paved shoulder. |
Numeric, positive |
|
Median Maximum Depth |
Depth of the median at the deepest point, near the optional key location. |
Numeric |
Behavior
This subassembly is inserted on both sides of attachment point, starting with the median links, using left/right median widths and other parameters. Edge of paved shoulder will be located (on both right and left sides) using Shoulder Height Offset parameter value. The finish grade of the shoulder is inserted for the given Shoulder Width and Shoulder Slope outward from the attachment point. The subbase link is inserted from the outer most point on the paved shoulders starting at the “Subbase Depth”, for left and right sides respectively, below the finish grade.
The Pave1, Pave2, and Base surface links are inserted parallel to the finish grade at the given depths. If the layer Extension values are non-zero, each layer is extended for the given distance beyond the shoulder hinge point. Each layer should be as wide as or wider than the one above it.
Finally, Barrier links are added from the end of the medians using the barrier bottom width, height, middle width, middle height and curb height parameters.
Superelevation Axis of Rotation Support
This subassembly works only with Roadway Types that have a Pivot Method of Median Edges and a Median Treatment of Maintain Median Shape. If you use this subassembly with any other Pivot Method or with Distorted Median Treatment, it will produce a result equivalent to Median Edges with Maintain Median Shape.
Layout Mode Operation
In layout mode this subassembly displays all links using the default values for various input parameters.
Point, Link, and Shape Codes
The following table lists the point, link, and shape codes for this subassembly that have codes assigned to them. Point, link, or shape codes for this subassembly that do not have codes assigned are not included in this table.
| Type | Codes | Description |
|---|---|---|
| P1 | Crown | Insertion point and typically at the centerline |
| P2, P3 | EPS | Edge of paved shoulder on top links |
| P4, P5 | Median | Edge of median |
| P6, P7 | EPS_Pave1 | Edge of paved shoulder on Pave1 |
| P10, P11 | EPS_Pave2 | Edge of paved shoulder on Pave2 |
| P14, P15 | EPS_Base | Edge of paved shoulder on Base |
| L1, L2, L17, L18 | Top | Top link on the median portion including barriers |
| L3-L7; L19-L23 | Barrier | Barrier Links |
| L8, L24 | Top, Pave | |
| L9, L25 | Pave1 | Bottom of first pavement layer |
| L10, L26 | Pave2 | Bottom of second pavement layer |
| L11, L27 | Base | Bottom of base course layer |
| L12, L14, L16 | SubBase | Bottom of subbase course layer |
| S1 | Pave1 | |
| S2 | Pave2 | |
| S3 | Base | |
| S4 | SubBase | |
| S5 | Barrier |
Coding Diagram
