Creates a Design Area Element that can be used to define slabs, walls, or any other planar surface. Takes a closed polyline as an input for the geometry. This closed polyline must be planar, but can lie on any plane.

Inputs

Outputs

To assign the more nuanced area element options, click the blue “Element Options” button at the bottom of the component. This will bring up the following window:

Area Assignment Options

1. Simple Meshing Options
   1. Auto Mesh: Check this box to auto-mesh the design area element.
   2. Mesh Size: The approximate mesh size for auto-meshing.
   3. Area Edge Treatment: Defines how points are laid out on edges.
      1. Allow Added Nodes on All Edges: Allows the auto-mesher to place additional nodes on all edges. This could lead to some nodes on adjacent edges not aligning. General connectivity will still be maintained, but this does not guarantee that every point will be connected at adjacent design area edges.
      2. Allow Added Nodes on Interior Edges Only: Allows the auto-mesher to place additional nodes on interior edges only. Interior edges are those defined by lines lying within the area element, interior boundaries (i.e. holes), etc. This ensures that nodes on adjacent design area edges will align, but does not ensure that nodes on interior edges will align with connecting elements.
      3. Prohibit Added Nodes on All Edges: Prohibits the auto-mesher from placing additional nodes on any edges. This ensures that all nodes on adjacent or intersecting design area edges will be connected. However, this could lead to the creation of elements with poor aspect ratios.
   4. Mesh at Intersecting Frames: Check to include intersecting frame elements in the auto-mesh, ensuring that intersecting frames are connected with the are mesh.
      1. Include Internal Frame Nodes: Check to include additional internal frame nodes in the mesh. These internal nodes include rigid end zone and reduced beam section nodes. This ensures complete connectivity with the frame element, but will produce significantly more elements as rigid end zones and reduced beam sections are typically very small compared to mesh size.
   5. Mesh at Intersecting Areas: Check to include intersecting areas in the auto-mesh, ensuring that intersecting design area elements are fully connected.
   6. Mesh at Intersecting Points: Check to include points that fall within the design area element in the auto-mesh.
   7. Allow Quad Elements: Makes the auto-mesher try to combine triangular elements into quadrilateral elements. This may result in significantly fewer elements, but forming quads takes time. Additionally, quadrilateral elements are generally more computationally intensive than triangular elements. And finally, the number of degrees of freedom remains the same, so the size of the matrix solution doesn’t change.
   8. Priority: Allows meshing priority to be set. The higher the value, the higher the priority. For example, a priority of 10 is higher than a priority of 5. The highest priority areas get meshed first. This is useful if you have areas that have different mesh sizes intersecting each other. Typically, you want areas with smaller mesh sizes to be meshed first.
2. Advanced Meshing Options
   1. Number of Refinements: Number of times the mesh is refined, prior to smoothing.
   2. Number of Smooths: Number of smoothing operations performed.
   3. Refine After Smoothing: Check to force a refinement after each smoothing operation.
   4. Conforming Delaunay: Check to force a conforming Delaunay mesh. See here for additional information regarding Delaunay Triangulation.
   5. Convex: Check to force a convex mesh.
   6. Quality Mesh: Check to enforce mesh quality provisions.
   7. Min Angle: Minimum angle that the auto-mesher targets.
   8. Max Angle: Maximum angle that the auto-mesher targets.
3. Behavior
   1. Include Plate Bending: Check to include plate bending behavior in the element formulation. If this is unchecked, the element is membrane only and cannot support any out-of-plane loads.
   2. Include Shear Deformation: Check to include the effects of shear strain energy across the thickness. If checked, uses a thick-shell formulation. If unchecked, uses a thin-shell formulation.
4. Design Material
   1. Material: Material to apply to the elements.
5. Element Stiffness Modifiers
   1. F11: Axial stiffness modifier in the local X-direction.
   2. F22: Axial stiffness modifier in the local 2-direction.
   3. F12: Shear stiffness modifier in-plane.
   4. M11: Bending stiffness modifier in the direction of the local X-axis (bending about the local Y-axis).
   5. M22: Bending stiffness modifier in the direction of the local Y-axis (bending about the local X-axis).
   6. M12: Twisting stiffness modifier.
   7. G13: Through-thickness shear stiffness modifier.
   8. Mass: Modifier to apply to the element mass.
   9. Weight: Modifier to apply to the element self-weight.