#### Further Information

In addition to our technical support (e.g. via chat), you’ll find resources on our website that may help you with your design using Dlubal Software.

Receive information including news, useful tips, scheduled events, special offers, and vouchers on a regular basis.

• ### How do I find the non-designable locations in the work window?

There are several ways to find the non-designable locations.

• If the location is selected by clicking the table row in the add-on module, it is indicated by an arrow in the graphic of the main program (see Figure 01). You can adjust the view by moving the add-on module window to the second screen, if necesary. Furthermore, there is the "Jump to Graphic to Change View" button available in the add-on module.
• If the add-on module window is closed, you can use the search function by clicking the menu Edit → "Find via Number." In this case, you can enter the FE node number noted previously.
• If you activate the results of the add-on module in the work window of RFEM and select the result display using "Values on Surfaces," you can select the "Notes Only" result option. The numbered notes are then displayed in the list at the bottom left of the screen.
• ### Is it possible to control the beam steering of an antenna in RF‑/TOWER Design?

Beam steering is the angular rotation of antennas under the effect of the present loads (wind, overload, earthquake, deformation, and so on). As an indication, for the GSM, the value of the beam steering must not exceed 1°. This limit of beam steering is often accessible in the clauses of the Technical Specifications of the project.
In RF‑/TOWER Design, it is possible to control the beam steering of antennas for the SLS design. To activate this rotation design of antennas, go to DetailsServiceability.

As soon as you select this check box, the antennas are available in Window 1.10.2 Serviceability of Antennas. Here, you can enter the angular rotation limit of each antenna.

After the calculation, the maximum ratio is displayed in Window 2.7 Design by Antenna.

• ### Why is the material property in the program different from the material property in the current standard?

004366

The reason for this is that the program allows you to select the materials from valid as well as from old ("invalid") standards.

In the program, the materials are stored with the material description and the standard. When selecting the desired material, it is necessary to pay attention to the material description and the standard to ensure that the selection is correct.

• ### In RF‑FOUNDATION Pro, I get Error Message No. 30195. What can I do?

The error message indicates that there was no option found to define the required reinforcement for the mats and rebars that you have selected.
After clicking OK, you will be automatically redirected to Window 1.3. Please select additional mats and/or rebars here, and then perform the design again.
• ### How is it possible to consider edge lamellas of a glued-laminated beam?

In the main program RFEM/RSTAB, it is first necessary to rotate the member about 90° so that the lamellas of the glued-laminated beam are lying edgewise, see Figure 01.

In order to also consider the on-edge position of the beam for the design in the RF‑/TIMBER Pro add-on module, increase the resistance for edgewise bending under National Annex Settins in the "Other Settings 2/2" tab, see Figure 02.

• ### RF-STEEL AISC add-module shows non-designable results for general cross-sections because of shear buckling checks according to Chapter G. How do I solve this?

When designing general cross-sections in the RF-STEEL AISC module, a "Non-designable" message is given for the design ratio. General cross-sections are defined in the program as user-defined sections or shapes which are not included in the specification. Though, some user-defined cross-sections can be designed under specific conditions. The warning message is displayed because shear buckling is not provided for general cross-section in the AISC 360-16 [1] Chapter G. More info on this topic can be found in the RF-STEEL AISC manual linked below.

This warning can be turned off in RF-STEEL AISC add-on module under the "Details" button > Shear Buckling > "Shear buckling warning for general cross-section."

• ### I have used the RF‑/DYNAM Pro add-on module to generate the governing result combinations of seismic loads. What is the next procedure to perform the design of the individual structural components?

With the Equivalent Loads and Forced Vibrations add-on modules, you can create the result combinations that contain the governing combinations of seismic loads. To perform the design using them, they have to be combined further on the basis of the accidental combination. This combination is defined, for example, in EN 1990, Section 6.4.3.4:

${\mathrm E}_{\mathrm d}\;=\;\underset{}{\sum_{}^{}\;{\mathrm G}_{\mathrm k,\mathrm j}\;+\;\mathrm P\;+\;{\mathrm A}_{\mathrm{Ed}}\;+\;}\overset{}{\underset{}{\sum{\mathrm\psi}_{2,\mathrm i}\;{\mathrm Q}_{\mathrm k,\mathrm i}}}$

This accidental combination has to be defined manually in RFEM. Make sure that (for a direction combination with the 100/30% rule), both created result combinations from RF‑/DYNAM Pro have to be added with the "OR" condition. Such a combination is displayed in Figure 02.

This accidental combination can then be used for further design. It is possible to evaluate the governing internal forces as well as to import and calculate this combination in the design modules.
• ### When calculating a case of RF‑/JOINTS Steel - Column Base, I get Message No. 48335 saying that the bending moment Mz exceeds 5% of the plastic moment resistance. What does it mean?

The analysis of a rigid column base is performed according to EN 1993‑1‑8 in the RF‑/JOINTS Steel - Column Base add-on module. The standard only provides the simple bending in the design format. The design can be performed for pure compression, tension, simple bending, or a combination of bending and tension, or bending and compression. If you click "Yes" to confirm the message, the add-on module performs all designs without taking into account the unsupported internal force Mz.
• ### Why is the shear stiffness reduced to 10% in the RF‑LAMINATE add-on module as well as for the orthotropic material model in RFEM for the shear modulus Gyz? I think the shear stiffness in the shear plane Gxy would have to be reduced here?

The reduction of the shear stiffness is caused by the fact that the fibers perpendicular to each other have a very small stiffness and a low strength. For this reason, the rolling shear strength of CLT panels is also very small.

In the case of cross-laminated timber plates, the glued sideboards are assumed on the boards. The boards are applied in the longitudinal direction along the x‑axis of the coordinate system (Figure 02). For the shear stresses in Figure 02, the shear stress τyz is thus opposed to the rolling shear strength.

The same applies to the shear stiffnesses. In the direction of the minor axis (yz‑ plane), the stiffness of the individual boards is considerably smaller than in the direction of the principal axis (xz‑plane) and also larger than in the xy‑plane. The coordinate system shown in Figure 02 should be placed on the boards in Figure 03.

• ### Which method of analysis is used for insulating glass?

If there is an insulated glass unit selected for the design in RF‑GLASS, the method of the large deformation analysis is set by default. Based on the existing gas volume in the space between glass panes, this method of analysis is also required and cannot be changed.

1 - 10 of 31

If not, contact us via our free e-mail, chat, or forum support, or send us your question via the online form.

#### First Steps

We provide hints and tips to help you get started with the main programs RFEM and RSTAB.

#### Wind Simulation & Wind Load Generation

With the stand-alone program RWIND Simulation, wind flows around simple or complex structures can be simulated by means of a digital wind tunnel.

The generated wind loads acting on these objects can be imported to RFEM or RSTAB.

#### Your support is by far the best

“Thank you for the valuable information.

I would like to pay a compliment to your support team. I am always impressed how quickly and professionally the questions are answered. I have used a lot of software with a support contract in the field of structural analysis, but your support is by far the best. ”