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Answer
A thread cannot be created by means of a function in the program. Here, you have to create this geometrically via nodes and lines. In the program, there is the option to create the turns by means of trajectory surfaces. However, you can use the copy and rotate function to quickly reach the destination. 
Answer
You can connect a rib member to a line on two surfaces with different thicknesses.
To determine the stiffness or the determination of internal forces, the eccentricity for the rectangular crosssection is determined in RFEM with the mean value of the two connected surfaces.
Figure 01  RFEM model of the rib with different plate thicknesses
For the design in RFCONCRETE Members, the addon module determines its own crosssection, which is displayed in the "1.4 Ribs" input dialog box of the addon module.
Figure 02  Dialog Box "1.4 Ribs" in RFCONCRETE Members
By clicking the "i" button (see Figure 02), you can open an info dialog box for the generated rib crosssection, in which all crosssection values, the position of the shear center and centroid, etc., which are applied for the design in the module, can be viewed.
Figure 03  Crosssection properties of rib crosssection in RFCONCRETE Members
If the "Effective Width" is adjusted in the "1.4 Ribs" dialog box (e.g. to 0.50 m), this has an influence on the crosssection applied in RFCONCRETE Members and its crosssection values.
Figure 04  Modified crosssection values of the rib crosssection
However, this has no influence on the stiffness or the determination of internal forces in the 3D model in RFEM.

Answer
Orthotropic surfaces are nonlinear and cannot be designed within the RFSTEEL Surfaces addon module. It is still possible to get the full stress analysis in RFEM which can be compared to the limiting stresses manually. Otherwise, the surface will need to be set to "standard" for it to be designable within the addon module.

Answer
Section F2 out of the AISC 36016 [1] states that doubly symmetric IShapes and Channels that are bent about their major axis must be compact sections in order to be designed. An example of this can be seen below.
Noncompact sections cannot be designed according to F2. Figure 2 shows a nondesignable section. 
Answer
In the ASCE 716, the conservative value for the Gustfactor, G, is 0.85 for rigid buildings. The engineer can calculate an alternative and more accurate value. The Gusteffect, G_{f}, for flexible buildings accounts for size and gust size similar to rigid buildings but also considers dynamic amplification including wind speed, natural frequency, and damping ratio.The Gustfactor G or G_{f}, is considered to be 1.0 in RWIND Simulation. The structure is rigidly simulated in the numerical wind tunnel. The loads which are transferred back into RFEM are applied to the elastic structure with true stiffness considered.To account for any value other than 1.0 for this factor, the wind load case factor can be adjusted in RFEM under the applicable load combination. 
Answer
Yes, the data is freely available. Use the following download option to load the presentations and finished models of the consultants. 
Answer
The shear correction factor is taken into account in the RFLAMINATE program using the following equation.
$k_{z}=\frac{{\displaystyle\sum_i}G_{xz,i}A_i}{\left(\int_{h/2}^{h/2}E_x(z)z^2\operatorname dz\right)^2}\int_{h/2}^{h/2}\frac{\left(\int_z^{h/2}E_x(z)zd\overline z\right)^2}{G_{xz}(z)}\operatorname dz$with $ \ int _ { h/2} ^ {h/2} E_x (z) z ^ 2 \ operatorname dz = EI _ {, net} $The calculation of the shear stiffness itself can be found on page 15 of the English version to the manual of RFLAMINATE as follows:For the 10 cm thick plate in Figure 1, the calculation of the shear correction factor is shown. The equations used here are only valid for the simplified symmetrical plate structures!Layer z_min z_max E_x (z) (N/mm²) G_xz (z) (N/mm²) 1 50 30 11000 690 2 30 10 300 50 3 10 10 11000 690 4 10 30 300 50 5 30 50 11000 690 $\sum_iG_{xz,i}A_i=3\times0,02\times690+2\times0,02\times50=43,4N$$EI_{,net}=\sum_{i=1}^nE_{i;x}\frac{\mbox{$z$}_{i,max}^3\mbox{$z$}_{i,min}^3}3$$=11000\left(\frac{30^3}3+\frac{50^3}3\right)+300\left(\frac{10^3}3+\frac{30^3}3\right)$$+11000\left(\frac{10^3}3+\frac{10^3}3\right)+300\left(\frac{30^3}3\frac{10^3}3\right)+11000\left(\frac{50^3}3\frac{30^3}3\right)$$=731,2\times10^6Nmm$$\int_{h/2}^{h/2}\frac{\left(\int_z^{h/2}E_x(z)zd\overline z\right)^2}{G_{xz}(z)}\operatorname dz=\sum_{i=1}^n\frac1{G_{i;xz}}\left(χ_i^2(z_{i;max}z_{i,min})\;χ_iE_{i,x}\frac{z_{i,max}^3z_{i,min}^3}3+E_{i,x}^2\frac{z_{i,max}^5z_{i,min}^5}{20}\right)$$χ_i=E_{i;x}\frac{z_{i;max}^2}2+\sum_{k=i+1}^nE_{k;x}\frac{z_{k,max}^2z_{k,min}^2}2$χ_{1} 13.75 10^{6} χ_{2} 8.935 10^{6} χ_{3} 9.47 10^{6} χ_{4} 8.935 10^{6} χ_{5} 13.75 10^{6} $\sum_{i=1}^n\frac1{G_{i;yz}}\left(χ_i^2(z_{i,max}z_{i,min})χ_iE_{i,y}\frac{z_{i,max}^3z_{i,min}^3}3+{E^2}_{i,y}\frac{z_{i,max}^5z_{i,min}^5}{20}\right)=$
8.4642 10^{11} 3.147 10^{13} 2.5 10^{12} 3.147 10^{13} 8.4642 10^{11} Total 6.7133 x 10^{13}$k_z=\frac{43,4}{{(731,2e^6)}^2}6,713284\;e^{13}=5,449\;e^{3}$$D_{44}=\frac{{\displaystyle\sum_i}G_{xz,i}A_i}{k_z}=\frac{43,4}{5,449\;e^{3}}=7964,7N/mm$This corresponds to the value output in RFLAMINATE (Figure 2). 
Answer
It is possible to display or calculate the stresses in RFEM as well as in the addon module by means of the following smoothing options:
 Constant on elements
 Not continuous
 Continuous within surfaces
 Continuous total
 Continuously by groups or Continuous by groups
To compare the results, the same display type and calculation type must be selected in RFEM and RFSTEEL Surfaces.
In RFEM, it is possible to do this in the Project Navigator Show → Results → Surfaces → Distribution of Internal Forces/Stresses (Figure 02). In RFSTEEL Surfaces, this can be displayed or changed in the Details → 'Options' tab (Figure 03).

Answer
To consider average regions when designing in RFLAMINATE, they must always be activated in the detail settings of the addon module. See Figure 01 with the detailed settings in RFLAMINATE for this. 
Answer
The zero coefficient of structural soil strength can be used for better convergence of deeper excavations or small loading. Damaged soil have no structural soil strength. Therefore, it better picture damaged subsoil in the upper layers with this function. The possible entry for the depth of the soil failure is from 0.0 m to 1.0 m.
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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 standalone 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.
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