# Access Hole Model \[SIG]

The Access Hole Model workflow item defines the geometry and finite element model of a bottom-flange access hole plate. Access holes are cutouts in the bottom flange of a steel girder that provide access for inspection and maintenance; this object builds the plate outline, the cutouts, the mesh, and the boundary conditions that are later loaded by an *Access Hole Load* case.

## General

**Plate Length:** Overall length of the bottom-flange plate along the girder longitudinal (X) axis.

**Plate Width:** Overall width of the bottom-flange plate transverse to the girder (Y axis).

**Plate Thickness:** Thickness of the bottom-flange plate used by the FE mesh surface.

**Plate Material:** Material assigned to the plate FE mesh. Required; exactly one material must be picked. Links to a `Material` library object.

**Mesh Size:** Maximum target element size used when meshing the plate surface.

**Mesh Option \[MeshAdapt/Automatic/Initial mesh only/Delaunay/Frontal-Delaunay/BAMG/Frontal-Delaunay for Quads/Packing of Parallelograms/Quasi-structured Quad]:** Meshing algorithm used when generating the surface mesh. The default is Quasi-structured Quad.

**Plate Chamfer (Length Direction):** Chamfer dimension applied at each corner in the longitudinal (length) direction. A value of 0 leaves a square corner.

**Plate Chamfer (Width Direction):** Chamfer dimension applied at each corner in the transverse (width) direction. A value of 0 leaves a square corner.

## Access Hole

**Access Holes:** Table of access-hole cutouts in the plate. Each row is edited through the access-hole parameter interface and contains the following sub-parameters:

* **Access Hole Shape \[Circle/Rectangle]:** Shape of the cutout.
* **Hole Diameter:** Diameter of the circular cutout (used when Shape is Circle).
* **Circle Segment:** Number of polyline segments used to approximate the circular cutout (used when Shape is Circle).
* **Access Hole Length:** Length of the rectangular cutout along the plate length direction (used when Shape is Rectangle).
* **Access Hole Width:** Width of the rectangular cutout along the plate width direction (used when Shape is Rectangle).
* **Corner Radius:** Rounding radius at each corner of the rectangular cutout (used when Shape is Rectangle).
* **Hole Offset X:** Offset of the hole center from the plate center along the plate length direction.
* **Hole Offset Y:** Offset of the hole center from the plate center along the plate width direction.

## Left Edge Boundary Conditions

Stiffness values applied along the left edge (the edge at `X = -Plate Length / 2`). Enter 0 for Free, -1 for Fixed, or a finite spring stiffness (translational stiffnesses use `ForcePerLength`, rotational stiffnesses use `MomentPerAngle`).

**Tx \[Free/Fixed]:** Translational stiffness along X on the left edge.

**Ty \[Free/Fixed]:** Translational stiffness along Y on the left edge.

**Tz \[Free/Fixed]:** Translational stiffness along Z on the left edge.

**Rx \[Free/Fixed]:** Rotational stiffness about X on the left edge.

**Ry \[Free/Fixed]:** Rotational stiffness about Y on the left edge.

**Rz \[Free/Fixed]:** Rotational stiffness about Z on the left edge.

## Right Edge Boundary Conditions

Stiffness values applied along the right edge (the edge at `X = +Plate Length / 2`). Same convention as the left edge — 0 for Free, -1 for Fixed, or a finite spring stiffness.

**Tx \[Free/Fixed]:** Translational stiffness along X on the right edge.

**Ty \[Free/Fixed]:** Translational stiffness along Y on the right edge.

**Tz \[Free/Fixed]:** Translational stiffness along Z on the right edge.

**Rx \[Free/Fixed]:** Rotational stiffness about X on the right edge.

**Ry \[Free/Fixed]:** Rotational stiffness about Y on the right edge.

**Rz \[Free/Fixed]:** Rotational stiffness about Z on the right edge.

## Top Edge Boundary Conditions

Stiffness values applied along the top edge (`Y = +Plate Width / 2`).

**Tx \[Free/Fixed]:** Translational stiffness along X on the top edge.

**Ty \[Free/Fixed]:** Translational stiffness along Y on the top edge.

**Tz \[Free/Fixed]:** Translational stiffness along Z on the top edge.

**Rx \[Free/Fixed]:** Rotational stiffness about X on the top edge.

**Ry \[Free/Fixed]:** Rotational stiffness about Y on the top edge.

**Rz \[Free/Fixed]:** Rotational stiffness about Z on the top edge.

## Bottom Edge Boundary Conditions

Stiffness values applied along the bottom edge (`Y = -Plate Width / 2`).

**Tx \[Free/Fixed]:** Translational stiffness along X on the bottom edge.

**Ty \[Free/Fixed]:** Translational stiffness along Y on the bottom edge.

**Tz \[Free/Fixed]:** Translational stiffness along Z on the bottom edge.

**Rx \[Free/Fixed]:** Rotational stiffness about X on the bottom edge.

**Ry \[Free/Fixed]:** Rotational stiffness about Y on the bottom edge.

**Rz \[Free/Fixed]:** Rotational stiffness about Z on the bottom edge.


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