The wall panel element allows you to easily model walls for in plane loads. Wall panel data may be viewed and edited in two ways: graphically in the Wall Panel Editor or in the Wall Panels Spreadsheet.
There are several graphic-editing features that make the creation and modification of models quite easy. Use the Insert and Modify menus or the Drawing Toolbar to use these features in the model view. To create new wall panels, you can draw them using a drawing grid or draw "dot to dot" existing joints. Once you have created these items you may use other graphic features to apply loads and set boundary conditions.
You can set many of the wall panel properties up front or you can modify these properties after you draw them. Modifying properties is discussed in the next sections. See the Wall Panels topic for information on wall panels and their properties.
The Draw Wall Panels 
button lets you graphically draw wall panels in your model. Enter the appropriate wall panel parameters, click OK and draw wall panels between existing joints or on the drawing grid. You will also notice that the coordinates of the joint or grid point that is closest to your cursor are displayed in the lower right hand corner of the model view. The new wall panels will be shown on screen and will be recorded in the Wall Panels Spreadsheet.
To actually draw a wall panel, you have two options. One way is to modify your Drawing Grid according to how you wish to lay out your wall panels and use the Create Wall Panels by Clicking on Grid Areas option. Wall panels can then be created by clicking in the grid areas formed by the intersecting grid lines. As you click on an area, a wall panel will automatically be created in that area. The second option is to create wall panels by drawing them one joint at a time. First click on the grid point or joint that you want to be the "A" joint for the plate, then the "B" joint, "C" joint, and "D" joint in either clockwise or counter-clockwise order. The wall panel will "stretch" like a rubber band as you draw from joint to joint.
Note:
The parameters shown are the same parameters that you would enter on the Wall Panels Spreadsheet.
To Draw Wall Panels
If there is not a model view already open then click 
on the RISA Toolbar to open a new view and click 
to turn on the Drawing Toolbar if it is not already displayed.
button and select the Draw Wall Panels tab. Then set the wall panel properties. To stop drawing altogether right click or press the Esc key.
Note
button. There are a number of ways to modify wall panels. You may view and edit the member data in the Wall Panel Spreadsheet, you may double-click a wall panel to view and edit its properties, or you can use the Modify Wall Panels tool to graphically modify panels.
The graphical Wall Panel Modify tool modifies the properties of wall panels that already exist in the model. To use this tool, specify the properties you want to change and then select the wall panels that you want to apply these changes to. Wall panels can be modified one-at-a-time by selecting the Apply Entries by Clicking option. This will change the mouse cursor to a modify tool which applies to any wall panels which you click on. A group of selected wall panels can be modified all at once by using the Apply Entries to All Selected option. See the Graphic Selection topic for more on selecting.
The Out of Plane Flip option will flip the openings and regions within the wall. If you draw in your openings opposite of what you meant then this tool can be useful.
The parameters shown are the same as those used to define new wall panels.
The Use? check boxes next to the data fields indicate whether the particular parameter will be used or not when the modification is applied. If the box next to a field is checked, that parameter will be applied to any selected wall panels. If the box is NOT checked, the parameter will NOT be applied, even if a value is entered in the field. This allows you to easily change one or two properties on wall panels without affecting all the rest of the properties. Note that if a no value is entered in a field (i.e. the field is blank) and the corresponding check box is checked, clicking “Apply” will have the effect of clearing the data for that field.
To Modify Wall Panels
on the RISA Toolbar to open a new view and click to turn on the Drawing Toolbar if it is not already displayed. 
button and select the Modify Wall Panels tab. Then set the parameters for the new wall panels. Check the Use? Box for the items to apply. Note
button.Another way of editing wall panels is through the Wall Panel Spreadsheet. This spreadsheet is accessible through the Data Entry Toolbar and includes data on two tabs: Primary and Advanced.
The following data columns hold the primary data for the wall panels:
You may assign a unique label to any or all of the wall panels. You can then refer to the wall panel by its label. Each label has to be unique, so if you try to enter the same label more than once you will get an error message. You may relabel wall panels at any time with the Relabel Wall Panels option on the Tools menu.
The A, B, C, and D joint entries are used to define the 4 corner joints of a wall panel. The joints must all lie on the same plane, be oriented parallel to the vertical axis and be entered in either a clockwise or counter-clockwise sequence. They can not be adjusted from the spreadsheet.
The material set label links the wall panel with the desired material defined on the Material Spreadsheet.
Note
The thickness field on the Wall Panels Spreadsheet is the thickness of the element. This thickness is constant over the entire element. Note that the thickness for Masonry and Wood wall panels are set in the Design Rules spreadsheet. For concrete and general material walls the value is defined here.
This allows you to choose a specific design rule from the Design Rules spreadsheet. The design rule is where you can specify very detailed information for the wall.
This shows the current panel for masonry and wood walls. Wood and masonry walls can require an iterative solution. This means that the panel properties used for a wall panel may change from solution to solution, so here is the place where that information is displayed. Note that the panel properties also show up in the output.
When you select a design rule for a wall panel, there may be a range of sheathing call-outs, stud spacings and bar/grout spacings. At the initial solution the program simply uses the first item in the list that meets the criteria of the design rule and then the optimization starts from there. This initial criteria is what will show up in the Panel/Spacing column. After you optimize your wall this panel criteria may update/change. If you want to reset all of these values to the original values, simply press the 
button when in the Wall Panels spreadsheet.
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This is a column specific to wood wall panels and allows you to choose which design method you choose to work with: Segmented, Perforated or Force Transfer. See the Wood Wall Panels topic for more information. These design methods are not applicable for concrete, masonry, or general wall panels.
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This is a factor specific to wood wall panels that allows the user to manually adjust the shear stiffness of a particular wall panel. Because the program uses a finite element solution the program does not automatically consider some contributions to the FEM deflections, such as nail slip. With this adjustment factor the user can match up the deflections from their hand calculations with the FEM joint deflections at the top nodes in the wall.
These values are considered for both masonry and concrete wall design and allow you to modify the stiffness of the wall for cracking considerations. This value will be multiplied by the Igross of the wall.
By default (if left blank) the program will use a value of 0.50. This value comes from Section 3.1.5.2 of the ACI 530-11 code. If you have performed a cracked section analysis or want to override this default you can input it directly here.
By default (if left blank) the program will use a value of 0.70.
For service level analysis, the level of cracking will be significantly less. Therefore, the stiffness used in your analysis should be representative of the reduced loading and reduced cracking. Per the ACI 318-14 Section R6.6.3.2.2 (ACI 318-11 Section R10.10.4.1), the program will account for this increased stiffness by applying a factor of 1.43 to the cracked section properties for any load combination that has the “Service Load” flag checked on the Design tab of the Load Combinations Spreadsheet
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This is the effective length factor and is available concrete, masonry and wood walls. If left blank this will be taken as 1.0.
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This input controls the Cm calculation for P-Little Delta calculations for concrete wall panels. If this is left blank the program will auto-calculate this value. See the P-LIttle Delta section of the Concrete Wall - Design topic for more information.
This column allows you define a wall panel as inactive or excluded. Please see the Inactive and Excluded Elements for more information.
The Wall Panel Editor allows the user to edit the detailed properties of a wall panel including openings
If the wall panel is drawn clockwise it will be drawn with the panel's local x-axis going from left to right. If drawn counter-clockwise the panel's x-axis will go from right to left and is presented here as though you are looking at the back side of the panel.
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Within the Wall Panel Editor, you have the option of adding rectangular openings to the wall panel. To draw an opening, select the Create New Openings 
button and then select two grid intersections which make up the two diagonal corners of your opening.
To exit this tool right-click your mouse.
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Within the Wall Panel Editor, you also have the option of creating different rectangular regions within your wall panel. Regions are used to further define areas of your wall panel for use in analysis/design. If you do not specify a region in a wall panel without openings, then the entire wall panel will be considered a region.
To automatically draw regions you must first have your openings input. Once you have that you can click the Generate Wall Regions Automatically
button and the program will define regions as we would expect a user to want them.
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button and redraw them manually. See below for more information on this.
To manually draw a region, select the Create New Regions 
button and use your cursor to select two grid intersections which make up the diagonal corners of the region. Similar to wall openings, local coordinates and region dimensions will be displayed in the lower left corner in the Wall Panel Editor. To exit this tool right-click your mouse.
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Within the Wall Panel Editor, all boundary conditions are applied as continuous along a wall panel edge. To set boundary conditions within the wall panel editor, select the Create New Boundary Conditions 
button, select your boundary condition criteria, and select Apply. To exit out of this tool right-click your mouse. You can also apply boundary conditions to your wall panel outside of the Wall Panel Editor as well, but this is the only place where you can define a continuous boundary condition.
For wood wall panels, hold downs and straps are used in the program as well. For more information on adding hold-downs and straps, see the Wood Wall - Design topic.
The drawing grid, which appears in the upper right corner of the Wall Panel Editor screen, gives the user options for drawing within the Wall Panel Editor window. The options include:
Snap Options allows you to provide snap points at the edges of the wall panel at quarter and third points.
Grid Increments allow you to set a drawing grid within the Wall Panel Editor separate from that in the main model view that you can snap to when drawing openings and regions. This field can work in two separate ways:
In addition to the wall panel editing tools, the Wall Panel Editor window includes the following view controls:
Delete allows you to delete openings, regions or boundary conditions from the wall panel.
Render will turn rendering of the current model view on or off, depending on the current setting.
Nodes will show any nodes that fall in the plane of the wall panel and allow you to snap to them when drawing regions or openings.
Drawing Grid will turn the display of the Drawing Grid on or off, depending on the current setting.
Detach Wall Panel From Diaphragm will allow you to click on a diaphragm in the editor to detach it from the wall. The detached diaphragm will then show up in gray.
Loads will turn the display of the wall panel loads on or off, depending on the current setting.
Redraw Full Wall View redraws the wall panel to fit within the Wall Panel Editor window.
Copy Current View makes a copy of the current view and saves it to the clipboard.
Print Current View prints your current wall panel view.
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When a wall panel is drawn it comes along with a set of local axes. If the wall is drawn clockwise versus counterclockwise it will change the direction of the local axes.
In most cases the local axes direction does not affect results. Here is a list where the local axis is important:
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Wall panels can be loaded either directly or indirectly from supporting other elements (other walls, columns, beams, etc.). Line loads and distributed loads can be applied directly to wall panels
In RISA-
Within RISA-
In the image above, the red color is an area of very low axial force in the wall. Thus, you can see that, due to plate distribution of force, there is still arching action taking place. This arching action, however, will not be immune to additional loads added to the wall or the opening being located lower in the wall (as is assumed with the idealized arching action in many texts). Thus, though your loads for lintel design may not be identical to what idealized methods might consider, this is a rational loading for the geometry and loading input on the wall panel.
At solution time, the wall panels will be automatically meshed into quadrilateral plate elements. Unlike the plate elements created directly by the user, the automatically generated plate elements are transient in the program and will not be saved in the input file.
The wall panel meshing is treated similar to analysis results. When the results of an analysis are deleted, the wall panel mesh is cleared to be re-built during the next solution. When a solution results file is saved, the meshed elements will be included in that file.
The global mesh size for the wall panels can be input on the Solution tab of the Model Settings. The smaller the mesh size, the more accurate the analysis will be. However, smaller mesh size will also lead to longer solution time and more memory usage. The default mesh size is 12 inches RISA-
Localized small mesh sizes are used in the lintel locations for masonry walls, in order to achieve more accuracy for the lintel forces.
By default, the plate elements associated with the wall panels are not visible to the user. The mesh can be turned on using the setting on the Panels tab of the Model Display Options. The Show Mesh check box will turn the display of the wall panel mesh on or off.
Note
Point constraints are the locations within the wall panel that require connectivity to the meshed plate elements. The program will automatically generate point constraints at the following locations:
1. Location of an existing joint on the wall panel edges, region boundaries and opening boundaries.
2. Where beams intersects the wall panels (out-of-plane) on the wall panel edges, region boundaries and opening edges.
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Line constraints are the locations within the wall panel that require continuous connectivity to plate edges rather than a single point. The program will automatically generate line constraints at the following locations:
1. Opening edges.
2. The edge and vertical centerline of a defined region.
3. Where a diaphragm intersects the wall panel.
In order to generate an efficient mesh that gives accurate results, it is critical to place the line constraints and point constraints correctly. If line constraints or point constraints are very close to each other, the auto mesher will be forced to generate small sized elements in order to satisfy the constraints. Therefore, a large number of plate elements will be generated and the solution will be slowed down significantly.
The following guidelines should be followed to ensure a quality mesh:
Example #1: Region Boundaries
In order to satisfy the line constraints required by the opening edge, region boundaries, and wall boundaries, the program is forced to generate very small meshes in the portion of the wall adjacent to these constraints.
Example #2: Poorly Located Boundary Conditions:
The left boundary of region R1 is at the vertical center line of a wall panel. At the same time, the user placed an external boundary condition at the bottom of the wall panel, which is slightly offset from the center line. In order to accommodate the line constraint of the region boundary and the point constraint of the external boundary condition, the automesher is forced to generate a very small mesh adjacent to these constraints.
If the distance between the line constraints and point constraints are smaller than the merge tolerance specified on the Model Settings (which defaults to 0.12 inches) then the auto-mesher will automatically snap the constraints together during the meshing. This can eliminate some of the meshing issues that occur in the examples above.