Form: Slab Design
Toolbar Button:
Use the Display menu > Show Slab Design command to access the Slab Design form and display in the active window slab design information. This command will be available only if the Run menu > Run Analysis & Design command has been executed.
Note: Slab design displays also can be accessed by expanding the Slab Design item under Named Displays on the Display tab in the Model Explorer window.
Design Basis and Display Type: Select the design basis and the display type from the drop-down lists. The design basis can be strip based (i.e., design strips) or finite element based (i.e., slab objects) design. If tendons are present in the model, the Display Type can be Strength Reinforcing, Stress Reinforcing, Stress Check – Transfer, Stress Check – Normal and Stress Check – Long Term, which allow numerical stress check values to be displayed at different stages. Strength Reinforcement is obtained from strength design. Stress Reinforcement is obtained from stress-based design. If tendon objects are present in the model, Enveloping Reinforcement is the larger of the Strength or Stress Reinforcement. If tendons are not present, the Enveloping Reinforcement is based on strength design.
Design Basis - Strip Based
Display Type - Design Reinforcement. When the Design Basis is set to Strip Based and the Display Type is set to Enveloping Reinforcement, Strength Reinforcement or Stress Reinforcement, strip-based design reports the quantity of rebar required across the entire strip as a rebar area or as a number of bars and bar sizes.
Impose Minimum Reinforcing check box. Check this check box to display the code mandated minimum reinforcing when it exceeds the required amount calculated by the program. This is applicable only when Enveloping Reinforcement is the Display Type.
Rebar Location Shown: Check the appropriate check boxes to show top or bottom rebar, or check both boxes to show both top and bottom rebar.
Reinforcing Display Type: Choose to display the rebar area or rebar of a specified size by selecting the appropriate option, and in the case of the rebar size, selecting the rebar number from the drop-down list.
Reinforcing Diagram: Choose to display the reinforcing envelope diagram (and use the default or specify a scale factor) or display the reinforcing extent, or display both by checking the appropriate check boxes.
Choose Strip Direction: Check the layer for which the design strip reinforcing should be displayed; the options may be selected alone or in any combination.
Models with Tendons. When tendons exist in the model, total results are always displayed on each strip.
Models without Tendons. When tendons do not exist in the model, the Show Total Results on Each Strip option and the Break into Column and Middle Strip Results option are added to the form.
Choose the Show Total Results on Each Strip option to show the reinforcing for the entire strip width.
Choose the Break into Column and Middle Strip Results option to display the reinforcing as calculated for the column and middle strip widths. The ratio of column and middle strips to the overall design strip width is set using the Design menu > Slab Design Overwrites > Strip Based command.
Display Options: Check the Fill Diagrams check box to show reinforcement using fill. Check the Show Values at Controlling Station on Diagram check box to display rebar at the controlling station.
Show Rebar Above Specified Value:
None option. When this option is selected, the program will show the required rebar.
Typical Uniform Reinforcing Specified Below option. Select this option to refine the rebar display based on user input and provide input in the Typical Uniform Reinforcing area of the form. Specify the typical rebar based on size or area and select or enter values in the top and bottom drop-down lists or edit boxes, and then accept the default spacing values or specify other bar spacing by typing directly in the edit boxes.
Reinforcing Specified in Slab Rebar Objects option. Select this option to base the rebar display on the definitions made when the rebar was drawn or added to the model.
Note: At times, it may be useful to specify a minimum reinforcement at a specified spacing and then specify the extra number of rebar, wherever needed.
Display Type - Stress Check. When the Design Basis is set to Strip Based and a stress-check option is selected, the strip-based design shows stress diagrams of the average stress across the width of the strip.
Stress Type Shown: Choose to display either tensile or compressive stresses. Stress diagrams are displayed for the top and bottom fibers of the slab along the length of each design strip.
Scaling: Scale the default plot size by entering a factor into the edit box (e.g., a factor of 3 will make the plot three times larger).
Choose Strip Direction: Check the layer for which the stress check stresses should be displayed; the options may be selected alone or in any combination.
Models with Tendons. When tendons exist in the model, total results are always displayed on each strip.
Models without Tendons. When tendons do not exist in the model, the Show Total Results on Each Strip option and the Break into Column and Middle Strip Results option are added to the form.
Choose the Show Total Results on Each Strip option to show the reinforcing for the entire strip width.
Choose the Break into Column and Middle Strip Results option to display the reinforcing as calculated for the column and middle strip widths. The ratio of column and middle strips to the overall design strip width is set using the Design menu > Slab Design Overwrites > Strip Based command.
Display Options: Check the Fill Diagrams check box to show reinforcement using fill. Check the Show Values at Controlling Station on Diagram check box to display rebar at the controlling station.
Plot Type: Choose to display either stresses or demand/capacity (D/C) ratios. Display the allowable limit lines by checking the Show Allowable check box.
Design Basis - Finite Element Based
Display Type - Design Reinforcement. When the Design Basis is set to Finite Element Based and the Display Type is set to Enveloping Flexural Reinforcement, Flexural Strength Reinforcement or Flexural Stress Reinforcement, the finite element based design shows the required rebar area intensity (rebar area/unit length) plotted as contours on the slab.
Contour Range. Use the Minimum and Maximum edit boxes to specify display of a specific contour range.
Contour Averaging at Nodes. Select if slab design should be averaged by Objects, by Selected Groups (as set by groups), or not averaged at all.
by Object - When this option is selected, stresses for the area elements associated with each area object are separately averaged. That is, the stresses for all are elements associated with area object 1 are averaged. Then the stresses for all area elements associated with area object 2 are averaged and so on.
by Selected Groups - When this option is selected, stresses for the area elements associated with all area objects in each selected group are separately averaged. Click the Set Groups button to select the group. For example, assume Group 1 includes area objects 1A and 1 B and Group 2 includes area objects 2A and 2B. The stresses for all area elements associated with the area objects in Group 1 (i.e., area objects 1A and 1B) are averaged. Then the stresses for all area elements associated with the area objects in Group 2 (i.e., area objects 2A and 2B) are averaged.
Reinforcing Direction and Location. Choose the direction and location of the reinforcing. The reinforcing can run along Direction 1 or 2 and along the top rebar or along the bottom rebar.
Show Rebar Above Specified Values.
None option. When this option is selected, the program will show the required rebar.
Typical Uniform Reinforcing Specified Below option. Select this option to refine the rebar display based on user input and provide input in the Typical Uniform Reinforcing area of the form. Specify the typical rebar based on size or area and select or enter values in the top and bottom drop-down lists or edit boxes, and then accept the default spacing values or specify other bar spacing by typing directly in the edit boxes.
Rebar Averaging at Peaks area and Averaging at Peaks check box. When this check box is checked, the program will average the reinforcing at peaks. When the Max. Averaging Width (ft) check box is checked, a maximum averaging value can be specified.
Reinforcing Specified in Slab Rebar Objects option. Select this option to base the rebar display on the definitions made when the rebar was drawn or added to the model.
Display Type - Stress Check. When the Design Basis is set to Finite Element Based and a stress-check option is selected, finite element based design shows stress contours on the slab. Note that the stress check displays are available only when there is prestressing in the model.
Contour Range. Use the and Maximum edit boxes to specify display of a specific contour range.
Contour Averaging at Nodes. Select if slab design should be averaged at by Objects, at Selected Groups, or not averaged at all. Click the Set Groups button to access the Select Groups form.
Stress Direction and Location. Choose the direction and location of the stresses. The stresses can run along Direction 1 or 2 and along the top face or along the bottom face of the slab.
Plot Type: Choose to display either stresses or demand/capacity (D/C) ratios.
Click the Apply button to update the display. This form will remain open until the Close button is clicked.
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