#### 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.

• ### Is it possible to design timber structures in RFEM or RSTAB?

Both RFEM and RSTAB are ideally suited for the structural analysis and design of timber structures .

###### Main Programs RFEM or RSTAB
The main programs RFEM or RSTAB are used to define structures, materials, and actions. In addition to the option to create spatial frame and truss structures, such as halls, RFEM also allows for plate, wall, and shell structures, and thus provides a more versatile option. It pays off if it is necessary to also carry out design in other areas, such as solid construction.

The RF-LAMINATE add-on module is only available for RFEM.

For both programs, Eurocode 5 with numerous National Annexes and other international standards are available.

###### Available Standards
• RF-/TIMBER Pro - Eurocode 5 for stress analysis, stability analysis, serviceability limit state design, and fire resistance design according to EC 5 or the Swiss standard SIA 265

• RF-/TIMBER AWC - American Standard ANSI/AWC NDS-2018 for ultimate limit state design, serviceability limit state design, and fire resistance design

• RF-/TIMBER CSA - Canadian timber standard CSA O86‑09 and CSA O86‑14 for ultimate limit state design, serviceability limit state design, and fire resistance design

• RF-/TIMBER NBR - Brazilian timber standard for ultimate and serviceability limit state designs

• RF-/JOINTS Timber - Steel to Timber
Design of indirect timber connections according to Eurocode 5 or ANSI/AWC NDS 2018.
• RF-/JOINTS Timber - Timber to Timber
Design of direct timber connections with slant screws
• RF-LIMITS
Among other things, it analyzes the load-bearing capacity of members, member ends, nodes, nodal supports, and surfaces. Furthermore, the library includes various fasteners by Würth SHIGA, Sherpa, Simpson StrongTie, and so on, as well as the ultimate load-bearing capacity for timber beams by Steico and Metsä Wood.
Only in Connection with RFEM:

RF-LAMINATE - Stress and deflection analysis of laminate surfaces

RX-TIMBER allows for design of timber structures without using RFEM or RSTAB.

If you have any question about the Dlubal Software programs and services, please do not hesitate to contact our sales department.
• ### My aim is to mesh a circular hole plate in a mapped way. Is it possible to generate such a mapped mesh in RFEM?

By using the FE mesh refinement, the program allows you to create a mapped FE mesh. The automatic FE mesh generator can thus be controlled to a certain extent. However, a specified mesh geometry cannot be set.
• ### How does the "Orthotropic Plastic" material model work in RFEM?

The material model according to Tsai-Wu unifies the plastic with the orthotropic properties. In this way, it is possible to specifically model the materials with anisotropic properties, such as plastics or timber. If the material is plastified, the stresses remain constant. The redistribution is carried out according to the stiffnesses available in the individual directions. The elastic area corresponds to the Orthotropic Elastic - 3D material model. For the plastic area, the yielding according to Tsai-Wu applies:

${\text{f}}_{\mathrm{crit}}\left(\mathrm\delta\right)=\frac1{\mathrm C}\left[\frac{\left({\mathrm\delta}_{\mathrm x}-{\mathrm\delta}_{\mathrm x,0}\right)^2}{{\mathrm f}_{\mathrm t,\mathrm x}{\mathrm f}_{\mathrm c,\mathrm x}}+\frac{\left({\mathrm\delta}_{\mathrm y}-{\mathrm\delta}_{\mathrm y,0}\right)^2}{{\mathrm f}_{\mathrm t,\mathrm y}{\mathrm f}_{\mathrm c,\mathrm y}}+\frac{\left({\mathrm\delta}_{\mathrm z}-{\mathrm\delta}_{\mathrm z,0}\right)^2}{{\mathrm f}_{\mathrm t,\mathrm z}{\mathrm f}_{\mathrm c,\mathrm z}}+\frac{{\mathrm\tau}_{\mathrm{yz}}^2}{{\mathrm f}_{\mathrm v,\mathrm{yz}}^2}+\frac{{\mathrm\tau}_{\mathrm{xz}}^2}{{\mathrm f}_{\mathrm v,\mathrm{xz}}^2}+\frac{{\mathrm\tau}_{\mathrm{xy}}^2}{{\mathrm f}_{\mathrm v,\mathrm{xy}}^2}\right]$

where:

${\mathrm\delta}_{\mathrm x,0}=\frac{{\mathrm f}_{\mathrm t,\mathrm x}-{\mathrm f}_{\mathrm c,\mathrm x}}2$

${\mathrm\delta}_{\mathrm y,0}=\frac{{\mathrm f}_{\mathrm t,\mathrm y}-{\mathrm f}_{\mathrm c,\mathrm y}}2$

${\mathrm\delta}_{\mathrm z,0}=\frac{{\mathrm f}_{\mathrm t,\mathrm z}-{\mathrm f}_{\mathrm c,\mathrm z}}2$

$\mathrm C=1+\left[\frac1{{\mathrm f}_{\mathrm t,\mathrm x}}+\frac1{{\mathrm f}_{\mathrm c,\mathrm x}}\right]^2\frac{{\mathrm E}_{\mathrm x}{\mathrm E}_{\mathrm p,\mathrm x}}{{\mathrm E}_{\mathrm x}-{\mathrm E}_{\mathrm p,\mathrm x}}\mathrm\alpha+\frac{{\mathrm\delta}_{\mathrm x,0}^2}{{\mathrm f}_{\mathrm t,\mathrm x}{\mathrm f}_{\mathrm c,\mathrm x}}+\frac{{\mathrm\delta}_{\mathrm y,0}^2}{{\mathrm f}_{\mathrm t,\mathrm y}{\mathrm f}_{\mathrm c,\mathrm y}}+\frac{{\mathrm\delta}_{\mathrm z,0}^2}{{\mathrm f}_{\mathrm t,\mathrm z}{\mathrm f}_{\mathrm c,\mathrm y}}$

You can imagine the yield criterion as an elliptical surface in a six-dimensional stress space.
If one of the three stress components is applied as a constant value, the surface can be projected onto a three-dimensional stress space. The projection of yield surfaces for normal stresses according to Tsai‑Wu: if the value for fy (σ) is smaller than 1, the stresses rest within the elastic area. The plastic area is reached as soon as fy (σ) = 1; the values greater than 1 are not allowed. The model behavior is ideal-plastic, which means there is no stiffening.
• ### Why is it not possible to design any LVL material according to the SIA 265 standard in RF‑/TIMBER Pro?

When selecting the standard SIA 265, RF‑/TIMBER Pro can only use the materials for the members to be designed that are also allowed in the standard. You can easily find the valid materials in the material library by using the filter of the standard.
• ### How can we view the database of RF-LAMINATE? We would like to check this up to date.

The easiest way is to start RFEM or the add-on module RF-LAMINATE and create at least one surface and at least one load case. After you have selected the surface and defined the load case for calculation, open the manufacturer's library (see Figure 1). There you can select a structure.

Afterwards you can check the material characteristics as well as the strengths (see picture 1 and picture 2).

There is already an interesting webinar on the topic of Design of cross laminated timber panels in RF-LAMINATE on our website.

• ### How is the coupling between the individual layers controlled in the RF‑LAMINATE add-on module?

Generally, the module assumes that there is a rigid coupling between the layers.

More information about the calculation with the RF‑LAMINATE add-on module can be found in the respective manual. This also explains special features of various material models (isotropic, orthotropic, and hybrid).

• ### Can I use surface releases to separate two overlapping surfaces?

You can use the surface releases, but you need to separate the overlapping part with an own surface. Overlapping surfaces should be avoided in general and can be checked by the "Model Check" (Tools → Model Check → Overlapping Surfaces). Please watch the video file (see link below) to see the approach. Alternatively you can add a "Contact Solid" between the two surfaces.

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. ”