# Bearing Seat \[CBG] This part can be utilized to define bearing seats between bearings and pier caps. Bearing seats provide a stable surface for bearings to function effectively and can be used to reduce elevation differences between girders. Currently, bearing seats are mainly used for 3D models and 2D CAD. They do not affect FEM, except for potentially changing node elevations. Any stiffness due to the bearing seat is not modeled in FEM. ## General **Insertion Points:** Used for specifying the bearing location and can be selected by using the three dots and the options ‘Pick...’ and ‘Select...’. **Type \[Rectangle/Step]:** This parameter is used to define the object type. The available options are Rectangle and Step. **Material:** The material definition for the bearing can be made using this parameter. Materials can either be imported or assigned from previously defined ones. **Bearing Seat Steps:** * **Length**: The length is defined by this parameter. * **Height**: The height is defined by this parameter. * **Geometry Option \[Flat/Sloped]**: This parameter is used to specify the geometry option, with 'Flat' and 'Sloped' available as selections. * **Height 1**: Only active when **Geometry Option** is set to 'Sloped'. Together with **Height**, it defines the top-of-step elevations at the two ends of the step: **Height** sets the elevation at the near end and **Height 1** sets it at the far end, producing a sloped step surface along its length. Ignored when the step is 'Flat'. **Width Computation \[User Input/Auto]:** The options ‘Auto’ and ‘User Input’ can be chosen. In the case of choosing the ‘Auto’ option, the object will be generated according to the pier cap's width along Y-axis. Otherwise, the width of the object will be generated according to the input for the ‘Width’ column. **Width:** If the ‘Width Computation’ parameter is set to ‘User Input,’ this column will be activated, allowing the user to specify the width of the bearing seat. **Length:** The length of the bearing seat along the X-axis. **Horizontal Offset:** When width computation is chosen as ‘User Input’, the horizontal offset value can be specified. This value indicates the distance from the center of the insertion point on the Y-axis direction. **Thickness Computation \[User Input/Auto]:** The options ‘Auto’ and ‘User Input’ can be chosen. In the case of choosing the ‘Auto’ option, the object will be generated according to the distance between the top of the pier cap and the bottom of the girder. Otherwise, the thickness of the object will be generated according to the input for the ‘Thickness’ column. **Thickness:** If the 'Thickness Computation' parameter is set to 'User Input,' this column will be activated, allowing the user to specify the thickness of the bearing seat. **Longitudinal Offset:** The longitudinal offset of the bearing seat from the insertion point reference. This parameter allows positioning the bearing seat along the bridge alignment direction. **Vertical Offset of Seat Bottom from Top of Cap:** The vertical distance from the top of the pier cap or abutment to the bottom of the bearing seat. A positive value positions the seat below the cap surface, while a negative value positions it above. ![image-20240903-074137.png](https://openbrim.atlassian.net/wiki/download/attachments/2348810297/image-20240903-074137.png?api=v2) ![image-20240903-075349.png](https://openbrim.atlassian.net/wiki/download/attachments/2348810297/image-20240903-075349.png?api=v2) ![image-20240914-144216.png](https://openbrim.atlassian.net/wiki/download/attachments/2348810297/image-20240914-144216.png?api=v2) ## IFC **Type \[IfcBridge/IfcBridgePart/IfcBeam/IfcColumn/IfcSlab/IfcFooting/IfcPile/IfcBearing/IfcReinforcingBar/IfcReinforcingMesh/IfcTendon/IfcMechanicalFastener/IfcAlignment/IfcPositioningElement/IfcKerb/IfcGuardrail/IfcSurfaceFeature/IfcElementAssembly/IfcCableSegment/IfcSensor/IfcDistributionElement/IfcPlate/IfcWall/IfcRail/IfcRoad/IfcDiscreteAccessory/IfcDistributionSystem/IfcMember/IfcBuildingElementProxy]:** Specifies the IFC entity type for export. Default value is IfcBearing. **Predefined Type \[CYLINDRICAL/DISK/ELASTOMERIC/GUIDE/POT/ROCKER/ROLLER/SPHERICAL/USERDEFINED/NOTDEFINED]:** Specifies the predefined type attribute for the IFC entity. Default value is USERDEFINED. **Parent \[BRIDGE/SUPERSTRUCTURE/DECK/SUBSTRUCTURE/FOUNDATION/APPROACH\_STRUCTURE/RETAINING\_STRUCTURE]:** Specifies the parent structural hierarchy element in the IFC model. Default value is SUPERSTRUCTURE. **Properties:** * **Ifc Value \[Text/Label/Number]**: This parameter specifies the IFC Value. The available options are 'Text,' 'Label,' and 'Number.' * **Text Value**: If the IFC Value parameter is set to 'Text,' its value is defined by this parameter. * **Number Value**: If the IFC Value parameter is set to 'Number,' its value is defined by this parameter. * **Property**: The property is specified using this parameter. * **Property/Set**: The property is specified using this parameter. ## Quantities **Rebar Density(per cubic yard):** The density of reinforcing steel per cubic yard of concrete. Used to calculate the rebar weight based on the bearing seat volume. **Rebar Weight:** The calculated rebar weight based on the rebar density and bearing seat volume. (Read-only) **Volume:** The total volume of the bearing seat concrete. (Read-only) **Weight:** The total weight of the bearing seat based on volume and material density. (Read-only) **Material:** Displays the material name assigned to the bearing seat. (Read-only) ## Geometry **Longitudinal Offset:** Offset of the bearing seat along the PGL from its default location. **Vertical Offset of Seat Bottom from Top of Cap:** Vertical distance from the top of the pier cap to the bottom of the bearing seat. Positive values lower the seat below the cap top. **Left Start Offset:** Horizontal offset at the left (downstation) end of the bearing seat. **Right Start Offset:** Horizontal offset at the right (upstation) end of the bearing seat. ## Referencing Objects **Pier Cap:** Pier Cap workflow item that references this bearing seat. (Read-only) ## Quantities **Rebar Density(per cubic yard):** Rebar density used to compute the bearing seat's rebar weight for takeoff. --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. 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