Slabs

Defining the Surface Reinforcement

To define the reinforcement of the slabs, right-click the 'Surface Reinforcements' folder in the navigator. Then select New Surface Reinforcement in the shortcut menu.

Shortcut Menu "Surface Reinforcements"

As no material has been defined for the reinforcing steel yet, select the Create a new material box in the 'Reinforcement' area. The 'New Material' dialog box is opened.

Dialog Box "New Surface Reinforcement"

To define a new material by using the library, click the button in the 'Name' area. In the 'Select Material from Library' dialog box, the 'Reinforcing Steel' material type is preset.

Using Library to Define Reinforcing Steel

Click the Reinforcing steel grade line in the 'Material Series to Select' area (1). Then select the Grade 60 steel grade in the 'Material to Select' area (2). When you click OK, you return to the 'New Material' dialog box where you can check the material properties.

Selecting Reinforcing Steel in Library

The Material Values tab manages all parameters relevant to the concrete design. Click OK to apply the new material to the reinforcement.

Material Values for Concrete Design

The reinforcement consists of size #3 rebars and 0.500 ft spacing by default. It is assigned to the top and bottom sides of a surface. Those rebars represent the primary (or principal) surface reinforcement. It runs parallel to the x-axis of the surface by default. Depending on the axes of the designed surfaces, the reinforcement is to be rotated when it is assigned to a surface (see below).

Change the bar size to #4(1). To add a secondary transverse reinforcement, select the Additional transverse reinforcement option (2). Change the size of the rebars from #3 to #4. Increase the spacing to 0.675 ft in the 's_90°' box.

In the bottom-right area of the dialog box, the values of the primary reinforcement (0.39 in²/ft) and of the transverse reinforcement (0.29 in²/ft) are specified.

Enter Slabs in the 'Comment' area (3) to label this type of reinforcement.

Defining Surface Reinforcement

To assign the reinforcement to the slabs graphically, use the button in the 'Assigned to Surfaces No.' area (4). The model view and the 'Surfaces Assignment' dialog box is presented.

Assigning Reinforcement to Slabs

Select the two slabs by clicking the surfaces nos. 4 and 5 one after another. If necessary, activate the 'Transparent Model' view by selecting the relevant option from the list button on the toolbar. Then click OK to return to the 'New Surface Reinforcement' dialog box.

Close the dialog box by clicking OK. The rebars are displayed on the two slabs.

Slabs with Defined Reinforcement

Adjusting the Design Properties

To check and adjust the design properties of the slabs, select the surfaces nos. 4 and 5 in the 'Navigator - Data' one after another while holding down the [Ctrl] key. Then right-click one of the selected surfaces to open the shortcut menu. Select the Edit option.

Editing Design Properties

When you enabled the concrete design in the 'Base Data' (see the 'Edit Model - Base Data' dialog box image), extra features were activated for the surfaces – the 'Design properties'. New tabs are thus available in the 'Edit Surfaces' dialog box to control the concrete design settings.

Design Properties Activated for Slabs with Extra Tabs

Concrete Cover

Select the Concrete Cover tab. 1.500 in thicknesses are shown as default values for top and bottom cover. Change both values to 1.000 in.

Concrete Cover Settings

Concrete Design Properties

Select the Concrete Design Properties tab next.

Real View to Check Reinforcement Direction

This tab controls the angle that defines the direction of the primary reinforcement within each surface. It is referred to the local axes of the surfaces. To check those axes, click the button in the bottom-right area (1) so that the model view is displayed in the dialog box.

When you open one of the lists in the 'Reinforcement Directions' area, you will find the 'First Reinforcement Direction in x' option available for selection. As the primary spanning direction is parallel to the y-axes of the two slabs, however, it is required to create a new direction. Select the New Reinforcement Direction option in the list (2) or click the button to the right. A new dialog box is opened.

Defining New Reinforcement Direction

In the 'Direction Type' area, select the First Reinforcement Direction in y option from the list. Click OK to close the dialog box and return to the 'Concrete Design Properties' tab.

Reinforcement Directions of Slabs

Select the 2 - First Reinforcement Direction in y option for the 'Bottom surface side', too.

Surface Reinforcement

Select the Surface Reinforcement tab next.

Surface Reinforcement

The '1 - On Surface | Rebar | No.: #4 | s : 0.500 ft' reinforcement is preset for the slabs.

Design Configurations

Finally, select the Design Configurations tab.

Strength Configuration for Slabs

The 'Slabs' configuration type is preset. It accounts for an optimization of the design internal forces and for the minimum reinforcement of slabs (see the Strength configuration for slabs image).

The 'Deflection' tab is not relevant because the Serviceability design was deactivated. Therefore, click OK to apply the modified rebar layout and close the dialog box.

Slab Reinforcement