Access Hole Model [TB]

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.