# Preguntas más frecuentes (FAQ)

#### Base de datos de conocimientos

En la página de "Base de datos de conocimientos", podrá encontrar muchos artículos técnicos, consejos y trucos que pueden ayudarle a solucionar sus trabajos de ingeniería estructural usando Dlubal Software.

#### Boletín de noticias

Reciba información de manera regular sobre noticias, consejos útiles, eventos programados, ofertas especiales y cupones.

• ### Which explicit method is used in the RF-DYNAM Pro - Nonlinear Time History add-on module?

FAQ 002376 ES Módulos adicionales RF-DYNAM Pro - Nonlinear Time History

#### Respuesta

The RF-DYNAM Pro - Nonlinear Time History offers, in addition to the implicit NEWMARK method of mean acceleration, also an explicit method. In the manual of this add-on module, it is mentioned that this is a solver which uses the central difference method.

It should be noted that not the "original" version of the central difference method is used here, but a modified form. The modified form is characterized by the fact that it is simply not a central difference when applying the speed difference. The following two equations show the applied speed and acceleration differences.

Speed: (no central difference)
${\dot{\mathrm x}}_{\mathrm n+\frac12}=\frac{{\mathrm x}_{\mathrm n+1}-{\mathrm x}_\mathrm n}{{\mathrm{Δt}}_{\mathrm n+{\displaystyle\frac12}}}$

Acceleration: (central difference)
${\ddot{\mathrm x}}_\mathrm n=\frac{{\dot{\mathrm x}}_{\mathrm n+{\displaystyle\frac12}}-{\dot{\mathrm x}}_{\mathrm n-\frac12}}{{\mathrm{Δt}}_\mathrm n}$

This approach leads to a faster convergence since it responds "faster" to changes in loading or structure (nonlinearities).
• ### For wall ends and wall corners, no soil contact stresses are deducted in RF-PUNCH pro, even though the type "Foundation" has been set. It is also nowhere possible to define that the soil contact stresses should be deducted. Why does this happen?

FAQ 002375 EN Módulos adicionales RF-PUNCH Pro RFEM 2D RFEM

#### Respuesta

If you perform a punching shear design for a wall corner or a wall end at a floor slab or foundation plate, this entry is not necessary.

Since the punching load is determined at a wall corner or a wall end from the shear forces in the control perimeter when performing the punching shear design, the ratio of the surface load is missing anyway within the control perimeter (up to the load application). Therefore, this entry is also not necessary in the 1.5 dialog box.

If you, however, perform the punching shear design for a single column at a foundation plate with the punching load from the normal force of this column, you can enter the "Deductible Surface Load" at the end of the dialog box "1.5 Nodes of Punching Shear - Node of Punching Shear - Details" which allows to determine ΔVEd.
• ### I have modelled a precast slab as "orthotropic surface". Can I use these surfaces also in reinforced concrete design?

FAQ 002374 EN Módulos adicionales RF-CONCRETE RF-CONCRETE NL

#### Respuesta

Yes, you can use "orthotropic surfaces" for the reinforced concrete design in RF-CONCRETE Surfaces.

If you only would like to carry out serviceability limit state designs, you do not have to define additional settings in RF-CONCRETE Surfaces concerning the surface type.

You need the RF-CONCRETE NL add-on module to perform the serviceability limit state designs. Select in the "serviceability limit state" tab (in the dialog box "1.1 General Data") the design method "Nonlinear...". See Figure 01.

You can then change the surface type to "Constant" in the dialog box "1.3 Surfaces" so that the serviceability limit state design is also possible here. See Figure 02.
• ### How can I enter a one-way continuous slab in RFEM?

FAQ 002373 EN Modelado | Estructura RFEM

#### Respuesta

It is possible to simulate one-way continuous slabs (e.g. precast slabs) by using the "orthotropy" of the surfaces.

You can set the stiffness type "Orthotropic" in the "Edit Surface" dialog box separately for each surface. See Figure 01.

In the "Edit Surface Stiffness - Orthotropic" dialog box, you can define the orthotropy type and select, for example "Effective thicknesses". See Figure 02.

You can then define the effective thickness in the local x and local y-direction of the corresponding surface in the "Effective thickness" tab. Moreover, you also have the possibility in this dialog box to define an effective thickness for the self-weight. See Figure 03.
• ### Is it possible to perform the structural analysis and design of containers with Dlubal Software?

FAQ 002372 EN General RFEM

#### Respuesta

With the FEA Software RFEM, it is possible to perform the structural analysis and design of containers (shipping containers, office containers, mobile homes, etc.).

RFEM offers member, surface and solid elements for detailed modeling. All components can be designed in the corresponding add-on modules.

• ### Why are wind and snow load generator greyed out in my RFEM/RSTAB file?

FAQ 002371 EN Modelado | Cargas RFEM RSTAB

#### Respuesta

The prerequisite for using both generators for wind and snow load are that you are working with the 3D model type because when working with a 2D model type, the program does not have the corresponding geomtrical parameters.
The model type has to be set in the "Edit Model - General Data" dialog box. The dialog is opened by right-clicking "Model Data", "General Data" in the Project Navigator - Data. The modeling may have to be adapted.
• ### I would like to activate my license (not necessary for USB dongles), but the "authorization dialog box" is not displayed when starting the program. How can I activate the dialog box?

FAQ 002326 EN-US Licencias y autorización

#### Respuesta

If the "Authorization" dialog box (see Figure 1) is not displayed when starting the program, an authorization file has been already imported. In this case, please select in the Help → Authorization menu Diagnostics (see Figure 2). Save the text file and open it. Open the path in the Windows Explorer which is shown at "PermDataDirectory" (see Figure 3). In this directory, you find the file AUTHORE.INI which needs to be deleted. When starting the program the next time, the authorization dialog box, as shown in Figure 1, will be displayed. To activate the license, select the "Use full version" option (internet connection required).

• ### How can installations be distributed via the network?

FAQ 002317 EN-US Instalación RFEM RSTAB SHAPE-THIN CRANEWAY RX‑TIMBER Glued‑Laminated Beam

#### Respuesta

The installation packages can be distributed with a MSI file (Windows Installer Package). It is necessary to extract the MSI file from the installation package.

You have to start setup.exe with the parameter "-E" (see Figure 1). For the example shown in the figure, the RFEM installation file has been copied to drive C:\. After the decompression, you find a new folder in the same path with the name "Dlubal_Program_Version Number_Architecture". For the example in Figure 1, a folder with the name Dlubal_RFEM_5.07.13.124218_64-bit has been created.

The installation can be started afterwards from this folder with the command "msiexec -i .msi" (see Figure 2). If the authorization file should be imported at the same time and if the language should be German, the command is as follows:

msiexec -i "Dlubal RSTAB 64-bit.msi" -passive -q TRANSFORMS=1031.mst AUTHORIZATION_FILE_PATH=\\[IHR SERVER]\AUTHOR.INI

If the command -q (=-quiet) is used, the installation is carried out without graphical user interface.

It should be ensured that the command prompt is started by right-clicking → Run as Administrator.

If the program language should be English, the parameter "TRANSFORMS=1031.mst" has to be deleted.

You can find detailed information about all commands and language IDs in attached "Software Deployment" document (see below).
• ### The Task Manager shows a usage of only 50% when calculating an RFEM file. Why does the calculation not use all kernels?

FAQ 002278 EN Cálculo

#### Respuesta

The calculation does use all kernels. Some processors (Intel Core i7, XEON...), however, support Hyper-Threading. This means that each physically available procesor core is split up into two virtual cores for applications. This aims at a better usage of the single units of the core. There are some applications which benefit from this and run faster. However, this is not the case for the computation kernel of RFEM. Therefore, the computation kernel of RFEM often only uses the physically available cores, and the Task Manager displays that the processor seems to only have a usage of 50%.

• ### Is the update installed over the new version or is a parallel version of the program created? What do I have to take into account?

FAQ 002268 EN Instalación

#### Respuesta

The version 5.x is installed in parallel in this case. You can use it in parallel or, if not desired, uninstall it. “Big” update versions (5.5.xx, 5.06.xx, etc.) are always installed in parallel while intermediate updates (5.07.x1, 5.07.x2, etc.) are installed over the previous version. The projects are imported of course.

If necessary, it is recommended to import the personal settings in the configuration manager before uninstalling the old version because they are not imported automatically during the big update.

1 - 10 de 390