# Hanger \[TB]

A vertical or inclined tension member that suspends the tie girder / deck from an arch rib. Hangers are the primary load path transferring deck and live-load reactions up into the arch; they are typically designed as tension-only members under AASHTO LRFD 6.8 (members in tension) with fatigue checks per 6.6.1.

## General

**Arch:** The arch rib from which the hanger hangs. Pick one previously defined **Arch**. Required.

**Girder:** The tie girder (or floor-beam girder) to which the bottom of the hanger attaches. Pick a sub-girder object. Required.

**Location Type \[Relative (0-1)/Station]:** Chooses how **Arch Location** and **Girder Location** are interpreted. **Relative** normalizes to 0 at the arch/girder start and 1 at the end. **Station** uses absolute X-coordinates.

**Arch Location (Relative/Station):** Location of the hanger's top on the arch. If Location Type is Relative, 0 is the first bearing of the arch and 1 is the second; values between 0 and 1 interpolate along the arch curve. If Location Type is Station, the value is the X station on the alignment.

**Girder Location (Relative/Station):** Location of the hanger's bottom on the girder. Same interpretation as Arch Location. The bottom point is placed at the top of the girder; if the girder carries a deck, the connection is lowered by half the deck thickness to sit at the deck mid-depth.

**Section:** The Section library object used as the hanger cross-section (typically a round bar, rope, or small rolled shape). Picks from **Sections**. Required. Drives tension-member capacity checks per AASHTO 6.8.

**Orientation Angle:** Rotation of the section about the hanger's local tangent (beta angle). Useful for orienting non-circular hanger sections.

## Offsets

**Vertical Offset (Arch):** Vertical shift (Z) applied at the arch-end connection, added to the interpolated arch point. Positive is upward.

**Horizontal Offset (Arch):** Transverse shift (Y) at the arch-end connection. Positive moves to the right when looking up-station (internal -Y application).

**Longitudinal Offset (Arch):** Longitudinal shift (X) at the arch-end connection. Positive moves up-station.

**Vertical Offset (Girder):** Vertical shift (Z) applied at the girder-end connection.

**Horizontal Offset (Girder):** Transverse shift (Y) at the girder-end connection.

**Longitudinal Offset (Girder):** Longitudinal shift (X) at the girder-end connection.

## 3D Detailing

**Start Face Skew Angle (X-Axis):** Rotation of the start-face (arch end) cutting plane about the local X-axis.

**End Face Skew Angle (X-Axis):** Rotation of the end-face (girder end) cutting plane about the local X-axis.

**Start Face Skew Angle (Y-Axis):** Rotation of the start-face cutting plane about the local Y-axis.

**End Face Skew Angle (Y-Axis):** Rotation of the end-face cutting plane about the local Y-axis.

**Hanger Opacity:** Display opacity in the 3D view, 0 (transparent) to 1 (opaque).

## FEA Settings

**Number of FE Segments:** Number of finite-element subdivisions along the hanger. Typically 1 for a simple tension strut; increase when intermediate nodes are required to attach lateral restraints or to capture cable sag in long hangers.

**Merge Intermediate Nodes to Nearest \[No/Yes]:** When **Number of FE Segments** is greater than 1, controls whether the intermediate nodes merge with any coincident mesh nodes. Endpoint nodes always merge. Only visible when Number of FE Segments > 1.

## Quantities

**Min Section Area:** Minimum cross-section area along the hanger. (Read-only, may be slow on recompute.)

**Max Section Area:** Maximum cross-section area along the hanger. (Read-only, may be slow on recompute.)

**Total Surface Area:** Total exterior surface area including end faces. (Read-only, may be slow on recompute.)

**Min Cross Section Perimeter:** Smallest section perimeter along the hanger. (Read-only, may be slow on recompute.)

**Max Cross Section Perimeter:** Largest section perimeter along the hanger. (Read-only, may be slow on recompute.)

**Volume:** Total volume of the hanger. (Read-only, may be slow on recompute.)

**Min Length Path:** Shortest path length. (Read-only, may be slow on recompute.)

**Length @COG Path:** Length along the section's center of gravity — typically equal to the straight-line hanger length. (Read-only, may be slow on recompute.)

**Max Length Path:** Longest path length. (Read-only, may be slow on recompute.)

**Weight:** Computed weight, Volume × material density. (Read-only, may be slow on recompute.)

**Material:** Material name assigned through the section. (Read-only)

**Section:** Section name assigned to the hanger. (Read-only)

## 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]:** IFC entity class used on export. Default **IfcElementAssembly**; switch to **IfcCableSegment** or **IfcMember** if a more specific class fits your IFC target.

**Predefined Type \[Abutment/Accessory\_Assembly/Arch/Beam\_Grid/Braced\_Frame/Cross\_Bracing/Deck/DilatationPanel/EntranceWorks/Girder/Grid/Mast/Pier/Pylon/Rail\_Mechanical\_Equipment\_Assembly/Reinforcement\_Unit/Rigid\_Frame/Shelter/SignalAssembly/Slab\_Field/SumpBuster/SupportingAssembly/SuspensionAssembly/TrackPanel/Traction\_Switching\_Assembly/Traffic\_Calming\_Device/Truss/TurnoutPanel/UserDefined/NotDefined]:** Predefined-type attribute of the IFC entity. Default **CROSS\_BRACING** — change to **SUSPENSIONASSEMBLY** or a user-defined value when more precise classification is needed.

**Parent \[Bridge/Superstructure/Deck/Substructure/Foundation/Approach\_Structure/Retaining\_Structure]:** Structural-hierarchy parent under which the hanger is nested. Default **SUPERSTRUCTURE**.

**Properties:** Custom IFC property entries attached to this hanger on export.


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