Slab-Wall Connections in RFEM 6
Technical Article
The properties of the connection between a reinforced concrete slab and a masonry wall can be correctly considered in the modeling using a special line hinge that is available in RFEM 6. This special type of a line hinge limits the transferable forces of the connection depending on the specified geometry, and thus the material cannot be overloaded. In this way, you can control the parameters of a line hinge to limit the transmission of moments. This is necessary for the slab-wall connections in masonry structures, as the moments are not transferred indefinitely here, but only depending on the axial forces.
In RFEM 6, line hinges can be defined using the “Insert” menu. They are also available as “Types for Lines” in the Data Navigator. The basic parameters and the definition of line hinges is described in detail in the Knowledge Base article “Line Hinges in RFEM 6”. Provided that the line hinge that represents the connection between a reinforced concrete slab and masonry wall, is not a common line hinge, but a special one, the defined parameters differ from the ones described in the above-mentioned article. The following article will show you the definition of a “slab-wall connection” using line hinges for the connection between the slabs and the exterior walls of the structure shown in Image 1.
Once you open the “New Line Hinge” dialog box via the “Insert” menu or the “Line Hinges” entry in the Navigator, the “Slab-wall connection” option becomes available in the “Options” section (Image 2). By activating this option, you will be able to control the parameters of the line hinge in order to limit the transmission of moments. This can be done in the “Slab-Wall Connection” tab that is available as soon as you select the corresponding check box. The parameters of a line hinge that represents the connection between a reinforced concrete slab and a masonry wall are (represented by) an “Offset” and a “Block width”. These parameters are also shown in Image 2, and their values are required to determine the correct hinge stiffness within the program.
As already mentioned, the program allows you to automatically determine the correct stiffness of your wall-slab hinge, based on the interaction diagrams representing various geometric situations. To do that, activate the “Masonry Design” add-on and assign the respective surfaces and lines by using the “Select Surfaces/Lines” button in the upper right corner of the “New Line Hinge” dialog box (Image 2). This allows you to select surfaces and lines in the RFEM working window, as shown in Image 3. Please note that you can select several surfaces and lines, as is the case in this example, where both the slabs (that is, Surface 10 and Surface 5) and the slab-wall boundary lines are selected at once.
Next, click the “Regenerates line hinges for walls attached to the slabs of this hinge” button at the bottom of the dialog box section (Image 4) to generate line hinges from the slab-wall connection and to show them in the “Generated Line Hinges” section of the “Slab-Wall Connection” tab. The generated line hinges will also be available in the list of line hinges (Image 4).
Please note that the generated line hinges are displayed in different colors; the reason for this is the fact that they are created as new types, which cannot be edited. However, the determined diagrams can be displayed as shown in Image 5, as well as printed out or/and exported to a spreadsheet, a printout report, PDF, and a file.
Finally, the generated slab-wall connections are available, as shown in Image 6.
Summary
RFEM 6 provides you with a special line hinge to model the connection between reinforced concrete slabs and masonry walls. All you have to do is to define the geometry, and the program helps you to limit the transferable forces of the connection depending on it. This is possible based on the interaction diagrams, which are applied automatically and used to determine the correct stiffnesses.
Author

Irena Kirova, M.Sc.
Marketing & Customer Support
Ms. Kirova is responsible for creating technical articles and provides technical support to the Dlubal customers.
Keywords
Masonry building Reinforced concrete slab Masonry wall Slab-wall connection
Links
Write Comment...
Write Comment...
Contact Us
Do you have further questions or need advice? Contact us via phone, email, chat, or forum, or search the FAQ page, available 24/7.

Generation of Snow Loads in RFEM 6 According to ASCE/SEI 7-16 and EN 1991-1-3
The effects due to snow load are described in the American standard ASCE/SEI 7-16 and in Eurocode 1, Parts 1 through 3. These standards are implemented in the new RFEM 6 program and the Snow Load Wizard, which serves to facilitate the application of snow loads. In addition to this, the most recent generation of the program allows the construction site to be specified on a digital map, thus allowing the snow load zone to be imported automatically. These data are, in turn, used by the Load Wizard to simulate the effects due to the snow load.
Associated Products