Girder Strand [SPIG]
- mert.goktas (Unlicensed)
- Dogukan Kilic
3D Reference
Pretensioning strands generally applied to the precast segments. In OpenBrIM, to specify the segments creating a Support Line to specify the start and end portions of the segments is beneficial for defining inputs.
Girder: Select the girder that strands are applied. Pretension loads are distributed to the this structural element.
Start Support Line: Starting support line for the precast segment.
Offset From Start Support/Insertion Point [ft]: Set the longitudinal offset from the Start Support Line, if applicable.
End Support Line: End support line for the precast segment.
Offset from End Support/Insertion Point [ft]: Set the longitudinal offset from the End Support Line, if applicable.
Strand Row Data: To view the inputs, click the three-dot menu, then select "Edit…". The description of the inputs is listed below.
Strand Data |
|
|---|---|
Type | Specify the type of the strand Straight or Harped. |
Inner strand spacing[in] | Specify the inner strand spacing. The distance is measured from the center of one strand to the center of the another strand. |
Outer Strand Spacing[in] | Specify the outer strand spacing between strands. The distance is measured from the center of one strand to the center of the adjacent strand. |
Horizontal Offset from Center[in] | Specify the horizontal offset to move center of the strand row. |
# of Strands | Specify the number of strands in a single row. |
Reference Edge | Specify the reference edge for Distance to Reference Edge input. |
Distance to Reference Edge @ Start[in] | Set the distance to reference edge. This distance is measured from the Reference Edge of the section to the center of the strand. Only avaliable when strand Type is Harped. |
Harped Distance[ft] | Distance of the harped location from the start |
Distance to Reference Edge @Harped Dist. [in] | Set the distance to reference edge. This distance is measured from the Reference Edge of the section to the center of the strand. Only avaliable when strand Type is Harped. |
Debonding Length (Start)[in] | Specify the debonding length of at the Start of the stra. |
Debonding Length (End)[in] | Specify the debonding length at the End of the strands. |
Properties
Material: Set the material for the strand.
Wobble Friction Coefficient [1/ft]: Pretensioning applications doesn’t include frictional losses that’s why this parameter has default zero value.
Curvature Friction Coefficient (1/rad): Pretensioning applications doesn’t include frictional losses that’s why this parameter has default zero value.
Jacking
Strand Type: Enter the strand type for the tendon. The strand type can be imported from the Properties section.
Jacking Method[Start/End/Start then End/ End then Start]: Specify the jacking method that is applied to the tendon. In the case of Girder Strand, start and end refer to downstation and upstation directions with respect to PGL.
Jacking Force From Start [kip]: Enter the start jacking force that is applied to the tendon. It must be specified, unless Jacking Method is selected End.
Jacking Force From End [kip]: End jacking force that is applied to the tendon. It must be specified, unless Jacking Method is selected Start.
FEA Settings
Load Dist. Elem. Type[FENodes/FELines]: This input affects the type of finite elements loads are distributed. FELines are used for beam elements.
Percent Loss(%): Set the percent loss for the long-term losses. This is an optional input. Users can leave this input as 0 and let OpenBrIM calculate the long-term losses using the CEB-FIB 1990 curve by running the time-dependent analysis. Alternatively, users can set an approximate value for the Percent Loss (%) to account for long-term losses, which will reduce the Jacking Force values of the tendon.