• Table - Browse to the superelevation table (path below). The superelevation tables are named by the "eMax Value"_"Design Speed".SUP, e.g. 08_40.sup. Select the appropriate table for your project.

"C:\NCDOT_V8_WORKSPACE\ROADWAY_STDS\English\geopak\Corridor_Modeling\Super_Data\AASHTO 2004\imperial"

 

• % Runoff on Tangent - For simple curves, 1/3 (33%) of the runoff is on the curve while the remaining 2/3 (67%) of the runoff is on the tangent. Enter 66.666667% in this field to be precise even though for display wise it is rounded up as 67%.

• Specify Runout - If known, specify a tangent runout distance.

• Non-Linear Curve Length -indicates, when checked on, that all super transitions are smoothed using a parabolic curve of the specified length.

• Interpolate Table Values - Determine if the superelevation rate is derived from an interpolation between two values or closest value from the superelevation tables.

• Transition Lengths Are

  Runoff (NCDOT preferred) - Specify the lengths derived from the superelevation tables are the runoff lengths, from zero percent cross slope high side to full super and vice versa. The tangent runout length is automatically calculated by continuing the same relative slope to normal crown (usually two increments from zero percent cross slope to normal crown high side).

  Total Transition (not recommended) - Specify the lengths derived from the superelevation tables are the combination of the runoff lengths and the tangent runout lengths, from normal crown to full super and vice versa.

• Load Values From Table - Determine the superelevation rate with the above settings.

• Update Geometry from Table - Prompt for the design speed used for the superelevation calculations in the wizard. Storing and updating the "Geometry" may be applicable to inRoads users and not pertinent to Geopak users.

  

• Next - Go to the next page of the Wizard, Superelevation Section Definitions.

2. Superelevation Section Definitions

• Add/Edit (Sections)- Define the superelevation control line for each section. For an undivided facility, the left and right sides are defined as one section. For a divided facility, the left and right sections are defined separately.

Name - Key-in name of superelevation section.

List all backbone points - List all points in template backbone. If unchecked, only the top surface backbone points are listed.

Crown Point - Select the section crown point on the template. Usually this is the PV1_PGL (undivided), LT_PV1_PGL (divided), or RT_PV1_PGL (divided) point.

Left Range - Select the left range point from the crown point. Usually it is the LT_PV1_OEOT point for an undivided facility. For a divided facility, it is the LT_PV1_OEOT point for the left section and the RT_PV1_PGL point (same as the Crown Point) for the right section.

Right Range - Select the right range point from the crown point. Usually it is the RT_PV1_OEOT point for an undivided facility. For a divided facility, it is the RT_PV1_PGL point (same as the Crown Point) for the left section and the RT_PV1_OEOT point for the right section.

Pivot Direction - Select the pivot direction for the section; from the Crown Point (recommended), Left Edge, Right Edge, Inside of Curve, or Outside of Curve.

Number of lanes - Select which column in the superelevation table is to be used in attaining the runoff length, 2 or 4 lanes. Note the 4-lane column is derived from taking the 2-lane column values and multiplying by it by 1.5 (lanes adjusted factor). It is critical to note this configuration in determining which multiplication factor should be applied in the next step.

Runoff Length Multiplication Factor - Specifies the factor applied to the runoff length from the selected table value. The below table are some suggested multiplication adjusted factors depending on how many lanes are rotated and which "Number of lanes" configuration was selected above.

# of Lanes Rotated (Each Side/Section)	Multiplication Adjusted Factor (2-Lane)	Multiplication Adjusted Factor (4-Lane)
1.0	1.00	0.67
1.5	1.25	0.83
2.0	1.50	1.00
2.5	1.75	1.17
3.0	2.00	1.33
3.5	2.25	1.50
4.0*	2.50*	1.67

* Intrapolated from AASHTO 2006 pg. 178 Exhibit 3-31.

Limit - Option to specify a range to apply the superelevation section or the entire chain (unchecked).

• Delete - Delete selected superelevation section.

• Edit (Superelevation) - Edit the superelevation rate and runoff lengths for each curve or spiral.

  

Percent Runoff on Tangent - Applicable to curve segments, not spirals. Value is derived from the first page in the Table Wizard setting.

Full Superelevation Rate - Option to override the superelevation rate derived from the tables.

Start Curve Transition:

Runoff Start Station - Override the starting runoff station (zero percent cross slope high side). Values are adjusted automatically when the runoff length changes with respect to the "Percent Runoff on Tangent" setting.

Runoff Length - Override the selected beginning runoff length from the tables.

Runout Length - Display only when a specified tangent runout length is entered. Otherwise this option is not displayed.

Use Spiral Length - Option is displayed only when spirals are present. Option to override the back spiral length.

Stop Curve Transition:

Runoff Stop Station - Override the stopping runoff station (full super). Values are adjusted automatically when the runoff length changes with respect to the "Percent Runoff on Tangent" setting.

Runoff Length - Override the selected ending runoff length from the tables.

Runout Length - Display only when a specified tangent runout length is entered. Otherwise this option is not displayed.

Use Spiral Length - Option is displayed only when spirals are present. Option to override the ahead spiral length.

Apply - Apply and save changes.

Previous - Go to the previous curve.

Next - Go to the next curve.

• Edit - Edit the superelevation alignment name and initial cross slope setting.

  

• Delete - Delete the selected superelevation alignment.

• Finish -Save the superelevation alignments and exit out of the Superelevation Wizard.

4. Fix Superelevation Overlap (Optional)

Section - identifies where the curve superelevation overlaps.

Shift Transition Onto Curve by - indicates the distance to move the entire transition to reduce the overlap.

Previous Curve - identifies the shift distance of the transition before the overlap.

Overlap - displays the remaining transition overlap. This field is display only.

Next Curve - identifies the shift distance of the transition after the overlap.

% Runoff on Curve - shows the % of runoff on the previous/next curves. This field is display only.

% Transition on Curve - shows the % of total transition on the tangent on the previous/next curves. This field is display only.

Reduce Transition Length by - specifies the amount by which to reduce the length of the transition in order to reduce the overlap. When this value is adjusted, the full super points remain fixed.

New Length - specifies the adjusted length of runoff on the previous/next curves.

Reduce Runout Length by - this field displays if runout length is specified separately. You can reduce runout lengths by a specified amount.

New Length - specifies the adjusted runout lengths.

Apply Full Super to Full Super Planar Transition - specifies, when checked on, that all points between the full superelevation points on two curves are deleted. This creates a planar transition between the full superelevation points of both curves.

Apply - applied the adjusted values to the current overlap. You cannot Undo this action.

First - displays the first superelevation overlap.

Back - returns to the previous overlap.

Next - proceeds to the next overlap.

Last - advances to the last overlap.

Close - closes the dialog.