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With regard to openings in 1D members, there are two issues that can be handled by the program:
splitting of shear and main reinforcement if it passes through the opening,
adding of reinforcement around the opening.
You may insert an opening into a 1D member. If such an opening is marked as "Use for analysis and design", then the reinforcement algorithm used in functions combined under tree branch 1D member > Redes (without As) can automatically adapt the reinforcement, so that it takes into account the opening.
It can be simply explained on an example. Let us assume a simple one-span beam with an opening somewhere in the middle of its length. If shear and longitudinal reinforcement has been inserted into this member, the program automatically splits the reinforcement. As a result:
two stirrup zones have been created – the first one going from the start-point of the beam to the face of the opening and the second one extending from the other face of the opening to the end-point of the beam,
the longitudinal reinforcement bars has been cut into two parts – with one part extending from the start-point of the beam to the face of the opening and the second one going from the other face of the opening to the end-point of the beam.
After the reinforcement has been inserted into a beam with an opening, it is possible to edit the size and position of the opening. The reinforcement is adapted accordingly after each such change. And vice versa: it is also possible to edit the reinforcement or add new bars, and all of them will take into account the existing opening.
This functionality (splitting the reinforcement) allows for an opening of any shape, e.g. rectangular, circular, I-shaped, T shaped, etc.
Reminder: In order to ensure that the reinforcement functions taken into account the openings defined in 1D members, the opening must have the option Use for analysis and design switched on.
The program allows you to input both shear and longitudinal reinforcement around openings. The programs analyses the shape of the opening and creates a new cross-section. If this cross-section shape is not present in the current reinforcement template library of the project, you must define a new reinforcement template for the new shape of the cross-section. Once this is done, the program is able to use the standard algorithm. The beam is divided to individual spans (e.g. first span = from the beginning of the beam to one face of the opening; second span = the opening; third span = from the face of the opening to the end of the beam).
Let us demonstrate the procedure on a typical example of a simple beam with a rectangular opening in the middle of the span. The beam has been already reinforced using the standard procedure.
Now, you have to add the reinforcement around the opening.
Open service Concrete Advanced.
Start function 1D member > Redes (without As) > Add reinforcement around opening (
).
Select the opening.
The program analyses the shape of the cross-section and opens a dialogue for input of a new stirrup template.
Define the shape of stirrups and confirm with [OK]. Close also the Stirrup shape manager.
A dialogue for input of longitudinal reinforcement template is opened on the screen.
Define the position of the main reinforcement around opening and confirm with [OK]. Close also the Longitudinal shape manager.
The reinforcement is added to the beam.
This functionality (input of reinforcement around opening) requires that the opening be only of a rectangular shape. Moreover, the opening must not be rotated.
Reminder: In order to ensure that the reinforcement functions taken into account the openings defined in 1D members, the opening must have the option Use for analysis and design switched on.
It is possible to define several openings in one member. If the openings were input separately, i.e. each opening on one call of Structure tree function 1D member > Modificator > Opening, there is no problem and the procedure described above can be applied on each of the openings.
However, if the openings were defined using the Repeat parameter, you must be aware of the consequences.
This way of input means that every time you select one of the openings, all of them are selected as they represent a single entity (multiple opening). This means that also the function for input of reinforcement around opening treats these openings as one entity.
As a result, when you select the opening, the program opens a special dialogue on the screen in which you can define the reinforcement template for each of the multiple openings.
