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Answer
The calculation of the results in grid points is important for displaying values on surfaces, among other things. You can find the information about grid points here.The problem is that in the case of complex structures and many load combinations, the calculation in grid points is relatively timeconsuming and therefore, it requires a large amount of memory. Even if you perform the calculation in FE nodes as shown in Figure 01, it is always necessary to additionally perform the calculation in grid points. Otherwise, the results cannot be displayed in grid points under Values on Surfaces.For complex structures, it is recommended to deactivate this option to perform a faster calculation. 
Answer
In the addon modules RF/TIMBER AWC and RF/TIMBER CSA, only rectangular and round crosssections can be designed at this time.
Figure 01  Crosssection design options in RF/TIMBER AWC and RF/TIMBER CSAWe are looking to expand the crosssection design capabilities in a future release similar to what the addon module RF/TIMBER Pro allows according to Eurocode.Therefore, design should be done manually for these types of crosssections according to the NDS or CSA standards. 
Answer
The RFTIMBER AWC module does not optimize crosssections for the Serviceability Limit State or the Fire Resistance design. Optimization is only calculated for the Ultimate Limit State design.Users must manually adjust the crosssection in RFEM or within the addon module and can export the crosssection back into RFEM. In either scenario, the model must be rerun in order to calculate the correct internal forces with the adjusted member size. 
Answer
Fire resistance design is not implemented in the RF‑LAMINATE addon module by default.However, you can calculate the charring rates yourself and consider them accordingly in the module. In the following example, this is explained on a simple plate.Structural system (Figure 01): Span 5 m
 Plate width 2 m
 LC1 (permanent) 1 kN/m² plus dead load
 LC2 (medium) 2.5 kN/m²
 3 layers
 S1 35 mm C24
 S2 20 mm C24
 S3 35 mm C24
Factors for fire resistance: Charring rate ß0 = 0.65 mm/min
 Pyrolysis zone k0d0 = 7 mm
 Charring time t = 30 min
 Effective thickness def=t ß_{0}+k_{0}d_{0}=30 min × 0.65 mm/min+7 mm = 26.5 mm
Remaining thickness of Layer 3 = 35 − 26.5 = 8.5 mm > 3 mm → thickness may be applied. (Figure 02)Because of the modified layer thicknesses, a new stiffness matrix results, which is applied in RFEM for accidental combinations with the characteristic stiffness values. For the ultimate limit state, the design values are calculated here (Figure 03). 
Answer
In principle, it is also possible to perform detailed analysis in RF‑LAMINATE. In the case of a very high shear distortion, for example, it can be reasonable to use orthotropic solids for modeling. The video shows a simple modeling and result evaluation of a layer structure by using solids.
A criterion, as of when is the modeling using solids useful, is the shear correction factor. Further information and other criteria can be found in the following FAQ:

Answer
The easiest way to consider this is to use the RF‑/JOINTS Timber  Steel to Timber addon module. For this purpose, the module decomposes the original connection, and creates a new structural system that considers the flexibility accordingly. In this case, the ultimate limit state, the serviceability limit state, and the accidental design situations are considered separately. 
Does the RF‑LAMINATE program consider the shear correction factor for crosslaminated timber plates?
Answer
The shear correction factor is considered in the RF‑LAMINATE addon module by 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 shear stiffness can be found in the English version of the RFLAMINATE manual, page 15 ff.For a plate with the thickness of 10 cm in Figure 01, the calculation of the shear correction factor is shown. The equations used here are only valid for simplified symmetrical plate structures!Layer z_min z_max E_x(z)(N/mm²) G_xz(z)(N/mm²) 1 50 30 11,000 690 2 30 10 300 50 3 10 10 11,000 690 4 10 30 300 50 5 30 50 11,000 690 $\sum_iG_{xz,i}A_i=3\times0.02\times690+2\times0.02\times50=43.4N$$EI_{,net}=\sum_{i=1}^nE_{i;x}\frac{\mbox{$z$}_{i,max}^3\mbox{$z$}_{i,min}^3}3$$=11,000\left(\frac{30^3}3+\frac{50^3}3\right)+300\left(\frac{10^3}3+\frac{30^3}3\right)$$+11,000\left(\frac{10^3}3+\frac{10^3}3\right)+300\left(\frac{30^3}3\frac{10^3}3\right)+11,000\left(\frac{50^3}3\frac{30^3}3\right)$$=731.2\times10^6 Nmm$$\int_{h/2}^{h/2}\frac{\left(\int_z^{h/2}E_x(z)zd\overline z\right)^2}{G_{xz}(z)}\operatorname dz=\sum_{i=1}^n\frac1{G_{i;xz}}\left(χ_i^2(z_{i,max}z_{i,min})\;χ_iE_{i,x}\frac{z_{i,max}^3z_{i,min}^3}3+E_{i,x}^2\frac{z_{i,max}^5z_{i,min}^5}{20}\right)$$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}}=7,964.7 N/mm$This corresponds to the resulting value in RF‑LAMINATE (Figure 02). 
Answer
In the case of the crosslaminated timber plates that are not glued to the narrow sides, and a walllike structural behavior, the torsion stress in the glued joints is often governing. This design is performed according to the following equation in compliance with the explanations in the literature reference below.$\eta_x=\frac{\tau_{tor,x}}{f_{v,tor}}+\frac{\tau_x+\tau_{xz}}{f_R}=\frac{\displaystyle\frac{3\ast n_{xy}}{b(n1)}}{f_{v,tor}}+\frac{{\displaystyle\frac{\frac{\partial n_x}{\partial x}}{n1}}+\tau_{xz}}{f_R}\leq1$where b is the board width,
 n is the number of board layers,
 n_{xy} is the shear in the layer plane,
 $\frac{\partial n_x}{\partial x}$ is the shear of board layers,
 $\tau_{xz}$ is the shear in the thickness direction,
 f_{R} is the rolling shear strength,
 f_{v,tor} is the torsional shear strength.
For the ydirection, the design is similar, but with the values for the y‑direction. 
Answer
These factors reduce the torsional stiffness D_{33} as well as the shear stiffness D_{88} of the corresponding stiffness matrix elements of a surface. Since crosslaminated timber is generally not glued at the narrow side, it is also not possible to transfer shear stresses to the timber narrow sides. Thus, the stiffness would be overestimated in this case. For this reason, the stiffness must be reduced accordingly.Some manufacturers have already provided us these values when delivering the layer structures. They result from the internal analysis. The explanation for determining the correction factors is covered in [1]. The analysis of this work has also been included in the Austrian Annex to EN 1995‑1‑1 [2]. The result is shown in Figure 02. The ratio of the timber width (a) to the timber thickness (t_{i}) can be taken from the respective approval. 
Answer
Yes, it is possible.
First, RF‑STABILITY (or RSBUCK in RSTAB 8) can be used to determine the effective lengths for a structural system and certain loading.They can then be imported in the "Effective Lengths" dialog box in RF‑/TIMBER Pro.
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First Steps
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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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