2191x
000547
2024-01-08

Shear Reinforcement

In the Shear Reinforcement tab, you can define the shear reinforcement that should be applied in the member shear design.

Important

The changes made in this tab only take effect if editing one member or identical members. If you edit several members with different properties (member length, cross-section), the entries cannot be applied.

Spans

In this dialog box section, you can define the stirrup reinforcement areas. There is only one entry preset, which represents a kind of "basic reinforcement". You can adjust this default setting and divide the one large "span" into sections (see the image Defining Shear Reinforcement). Use the New button at the end of the list to create new items.

Info

You can define the spans as overlapping or closed to each other. In the case of overlapping spans, the provided reinforcement area [cm²/m] is added and the sum is applied in the design.

For the graphical display of the stirrup reinforcement, it may be necessary to specify an "offset" for the edge Border Distances of Stirrups.

Parameters

In this section, you can define the shear reinforcement properties. The parameters always refer to the span selected in the "Spans" list.

Base Data

Select the "stirrup type" from the list. There are various stirrup shapes available.

Info

Not all stirrup types are applied in the torsion design. This depends on the stirrup shape – closed or open – and the specifications of the standard, which only permits certain types of U-locks for the torsion design.

Assign material to the shear reinforcement. If you have already defined the suitable reinforcement steel in the model, you can select it in the list. Otherwise, you can use the Edit Object button in the text box to create a new material by opening the New Material dialog box, where you can access the material library.

Stirrup Parameters

Specify the "bar diameter" ds,st of the stirrups, the distance ss,st between the stirrups, or the number ns,st of the stirrups in the span.

Usually, you only enter the stirrup diameter ds,st and the spacing ss,st. The amount of stirrups is obtained automatically. Anyway, you can also specify the number of stirrups ns,st. The program determines the proper distance for the span.

The reinforcement area of the provided stirrup reinforcement is shown in the category below.

Reinforcement Areas

Here, you can see the reinforcement area that results from the "Stirrup Parameters" entries. As an alternative, you can enter the reinforcement area asw directly in [cm²/m]. Based on this entry, the program determines the required distance ss,st and the resulting number ns,st of stirrups. The diameter ds,st remains the same.

Span Location

In this category, you specify where in the member the "span" with the stirrup reinforcement should be arranged. You can define this position with a "reference" to the start, the end, or the x-location. Select the corresponding option in the list to define the reference point for the span location.

Furthermore, you can use the "definition format" to control whether to define the distances absolutely in length units, or relatively in percentage.

Enter the "start" x1 and the "end" x2 of the span. The "span length" ls represents the length of the stirrup section in the member.

Border Distances of Stirrups

The "layout rule" controls how the stirrups are positioned at the edges of the span. There are several options available.

With the default setting "Start equals End", the program determines the remaining length from the number ns,st and the stirrup distance ss,st that is applied equally to the start and the end of the span. The text boxes for Δi and Δj are locked.

The other options allow you to manually define the border distances of the stirrups:

  • "Start defined": Enter the Start offset Δi that defines the position of the first stirrup in the span. The distance Δj at the end of the span is determined automatically; this value is not editable.
  • "Start = Rest length to stirrup distance": This option is not possible for the first span, only for the following spans. Using this rule, the distances Δi and Δj are determined automatically; the values cannot be edited. If you clear the previous span, the option is automatically changed to "Start defined" and the previously determined value is entered as the start offset Δi.
  • "End defined": Enter the end offsetΔj that defines the position of the last stirrup in the span. The distance Δi at the end of the span is determined automatically; this value is not editable.
  • "End = Rest length to stirrup distance": The program does not apply any start offset. The possible number of stirrups ns,st is determined based on the stirrup distance ss,st, and the remaining length at the end of the span is provided.
Info

In the case of a continuous beam consisting of several members, you should create a member set and design this instead of the individual members.

Information

Finally, here is the following information about the stirrup reinforcement of the current span:

  • Length of one stirrup Lst,1
  • Length of all stirrups Lst as a sum
  • Weight of one stirrup Wst,1
  • Weight of all stirrups Wst as a sum

Graphic

In both graphic areas of the tab, you can see the reinforcement displayed graphically. You can see the member section on the right, and the longitudinal section below. Your entries are implemented dynamically, thus providing you with a perfect control option.

Section

The graphic to the right shows the cross-section of the member with the stirrup and longitudinal reinforcement defined. The concrete cover is shown in the reinforcement layout. The cross-section graphic also shows the local axes z and y of the member.

The cross-section graphic refers to the reinforcement at "Location x" along the member specified in the text box below the graphic. With the default setting x = 0.000 m, the reinforcement is displayed at the member start. To display the reinforcement at a different member location, enter the corresponding distance. Location x is then indicated by an arrow in the longitudinal section.

The buttons below the graphic have the following functions:

Model View Switch between the section graphic and the model view
Filter Show only the longitudinal reinforcement specified in the Positions list.
Show Axis System Display or hide member axes
Show Dimensioning Display or hide the cross-section dimensions
Direct Print Various options of printing the graphic

Longitudinal Section

The graphic in the lower part of the dialog box shows the longitudinal section of the member, including the defined stirrup and longitudinal reinforcement, as well as the support symbols from the defined effective lengths and design supports.

To work in this graphic area, you can use all mouse functions described in the RFEM manual, Chapter Graphic Control. This allows you to zoom in on the reinforcement of the member or display it spatially.

The buttons next to the graphic have the following functions:

Axonometric View - List Set various view types
View in Direction of Member Axis View in different member axis directions
Transparent Model List View as wireframe model, solid model, or transparent model
Dimension List Show and hide various auxiliary and model objects
Real Shape Show the member symbolically in horizontal position or in real position
Direct Print Various options of printing the graphic
Reinforcement Layout Opens the Reinforcement Layout
Show Whole Model window to display full view of the member.