Bracing
Girders: Choose the two girders that are connected by the cross frame.
Skew Angle: A positive skew value rotates the cross frame in a clockwise direction, while a negative skew value rotates it in a counterclockwise direction. It is important to remember that the cross frames are positioned at the specified station along a line perpendicular to the PGL, which is then rotated according to the entered skew value.
Station[Start/End] : Enter the station along the PGL. When dealing with curved girder bridges, collecting distance along the girder length can lead to different inputs for the right and left girder that are connected by cross frames, causing ambiguity. Therefore, collecting the station along the PGL is a more reliable solution to avoid such issues. Furthermore, since cross frames are typically continuous in the transverse direction, entering the same station for all cross frames ensures that their locations are consistent between each girder.
The same principle can be applied for skewed cross frames. If the user enters the same station and skew values for the cross frames between Girder 1-2, Girder 2-3, and Girder 3-4, it ensures continuity between the cross frames. It should also be noted that the cross frames are positioned along a line perpendicular to the PGL, which is rotated according to the entered skew value.
Inaccurate finite element models and disconnected nodes/elements in the cross frame can occur if the entered station values are not >= the girder start station or <= the girder end station. This can cause stability issues in the finite element model. To ensure correct station input, users should select the start/end options from the station input. This approach is especially recommended for cross frames located at the beginning or end of girders.
Section: Assign a section for the bracing, which can be imported from the AISC database by the users.
Horizontal Offset from Edge of Web: This parameter can be used to specify the horizontal offset value for the custom bracing in the transverse direction, relative to the edge of the web.
Vertical Offset from Top of Web: This parameter can be used to specify the vertical offset value for the custom bracing, relative to the top of the web in the vertical direction.
Type[Truss/Beam]: The finite element representation is in the form of a truss or beam.
Orientation Angle[0/90/180/270]: Specify an angle for the bracing to rotate around its longitudinal axis.
Gusset Plate
Top Gusset Plate: A section for the top gusset plate can be assigned using this parameter.
Top Plate - Vertical Offset from Top of Web: The location of the top gusset plate with respect to the top of the web along the vertical direction can be defined using this parameter.
Top Plate - Horizontal Offset from Edge of Web: The location of the top gusset plate with respect to the edge of the web along the horizontal direction can be defined using this parameter.
Stiffener
The parameters listed below are used for 3D representation. While stiffeners do not have finite element models (FEM) and do not provide additional stiffness to the elements, they can still be applied as weight loads, depending on user-defined settings and specifications.
Stiffener Used [YES/NO]: If this parameter is set to 'YES,' the user can define additional parameters for stiffeners. If it is set to 'NO,' the other parameters will be marked as not applicable (N/A).
Vertical Stiffener Thickness: The thickness of the stiffener can be adjusted using this parameter.
Vertical Stiffener Width: The width of the stiffener can be adjusted using this parameter.
Material: The material definition for the stiffener can be made using this parameter. Materials can either be imported or assigned from previously defined ones.
FEA
Axial Rigidity Coefficient: This parameter specifies the axial rigidity coefficient of the bracing.
0 Comments