PGSuper
4.1
Precast-prestressed Girder Bridges
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The roadway profile is defined by a series of grade breaks (PVI) and vertical curves.
The profile begins with a reference point before the start of the bridge and then is defined by a sequence of vertical curves.
The entry grade of the first vertical curve and the exit grade of the last vertical curve are projected backwards and forwards along the profile.
Item | Description |
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Station | Station of the reference point |
Elevation | Profile elevation at the reference point |
Grade | Profile grade at the reference point in the direction of increasing station |
Vertical Curves | The vertical curves for this profile |
[Add] | Adds a vertical curve |
[Remove] | Deletes the selected vertical curves |
[Sort] | Sorts the vertical curves based on PVI Station |
Vertical curves are defined by the following parameters:
Item | Description |
---|---|
PVI Station | Point of Vertical Intersection station |
Exit Grade | The profile grade at the exit point of the vertical curve |
L1 | Distance from the beginning of the vertical curve to the PVI, or the total length of the vertical curve if L2 is left blank |
L2 | Distance from the PVI to the end of the vertical curve. |
NOTE: The PVI of the first vertical curve can be used as the Reference Point
NOTE: The exit grade of the previous curve is taken to be the entry grade of the next curve.
NOTE: The total length of the vertical curve is L1 + L2.
NOTE: For symmetrical vertical curves, enter the total curve length as L1 and leave L2 blank.
NOTE: Leave L1 and L2 blank to define a point of vertical intersection (PVI) for a grade break.
NOTE: While grade breaks do occur, they are not common. When a grade break is modeled, a warning will be put in the Status Center telling you that a zero-length vertical curve has been modeled. If you intended to model a grade break then no action is necessary. If you meant to model a vertical curve, then this status item will alert you to the input error.