Punching Reinforcements

The "Punching Reinforcements" allow you to define how to carry out the reinforcement against punching in a surface. The parameters of perimeters and legs, like the surface reinforcements, are types that you can then assign to the corresponding nodes. The options for reinforcement layout comply with the design standard.

Input Options

The program provides several options for entering punching reinforcements.

Shortcut Menu of Navigator

In the "Navigator – Data", right-click the Punching Reinforcements category. Then, select New Punching Reinforcement from the shortcut menu.

Defining Punching Shear Reinforcement via Navigator Shortcut Menu

Table

In the table, set the Structure main category and the Types for Concrete Design subcategory. Double-click an empty row in the Punching Reinforcements worksheet.

Defining Punching Shear Reinforcement via Table

Node Property

You can create a new punching reinforcement directly as a property of a node. Open the Edit Node dialog box. In the "Design Properties" section, select the Punching Design check box, and then switch to the Concrete Design – Punching Node tab.

Defining Punching Shear Reinforcement in Dialog Box "Edit Node"

Main

In the Main tab, you can define the main specifications of a punching reinforcement.

New Punching Shear Reinforcement | Main

Parameters

Material

Assign material to the punching reinforcement. If you have already defined a suitable reinforcement steel in the model, you can select it in the list. Otherwise, you can use the button to create a new material by opening the New Material dialog box, where you can access the material library. You can also access this library directly by using the button. The "Reinforcing Steel" material is preset here.

Use the button to change the material that has already been assigned. The button allows you to graphically transfer the reinforcing steel from another surface.

Bar Diameter

Define the diameter d_s of the reinforcement stirrups. Several options are available for selection in the list. However, the rebar diameter can also be user-defined.

Categories

Type

The type describes the geometric position of the punching reinforcement. For the design according to EN 1992, only the "Vertical" option is currently available. Thus, the reinforcement legs are placed without a (sloping) inclination.

If the design is based on ACI 318 and CSA A23.3, the following options are selectable in the list:

• Vertical | Stirrup
• Vertical | Multiple legs
• Vertical | Crosstie
• Double-headed studs
• Headed studs with base rail

The individual types are illustrated in the dialog graphic.

Distances

Define how the punching reinforcement legs are distributed in perimeters. For the design according to EN 1992, two options are available in the list:

• Uniform
• Differently

If the design is performed according to ACI 318 and CSA A23.3, only a constant distribution is possible.

In the Placement tab, you can then define the reinforcement arrangement in detail.

Placement

The type describes where the punching shear reinforcement is inserted: For the design according to EN 1992, the stirrups are arranged “radially” in the perimeter sections. If the punching shear design is performed according to ACI 318 and CSA A23.3, the reinforcement elements are placed “axially.”

Placement

In the Placement tab, you can define how the punching reinforcement is arranged. The input options are aligned with the specification in the Categories section of the "Main" tab.

Uniform

In the case of a constant arrangement, the punching reinforcement is distributed uniformly in the individual perimeters.

Punching Shear Reinforcement with Constant Distribution

Define the number of perimeters n_p and the number of legs in each perimeter n_l. Thus, an equal number of stirrups is placed in each perimeter.

The perimeter spacing can either be determined automatically as "Multiple effective depth (k * d)" or defined "Absolute" with user-defined spacing. The parameters are shown in the dialog graphic.

Differently

For the design according to EN 1992, the punching reinforcement can also be arranged by user-defined settings.

Punching Shear Reinforcement with Different Distribution

Define the number of legs n_l and the spacing k_sr of the perimeter in the table. Each line describes the parameters of a perimeter.

If you change the perimeter distance to "Absolute" in the lower part, you can define the distances between perimeters s_r by entering lengths.