Global 3D calculation of the global model, where the slabs are modeled as a rigid plane (diaphragm) or as a bending plate
Local 2D calculation of the individual floors
After the calculation, the results of the columns and walls from the 3D calculation and the results of the slabs from the 2D calculation are combined in a single model. This means that there is no need to switch between the 3D model and the individual 2D models of the slabs. The user only works with one model, saves valuable time, and avoids possible errors in the manual data exchange between the 3D model and the individual 2D ceiling models.
The vertical surfaces in the model can be divided into shear walls and opening lintels. The program automatically generates internal result members from these wall objects, so they can be designed as members according to any standard in the Concrete Design add-on.
With Dlubal Software, you always have an overview, regardless of whether your projects are from the reinforced concrete, steel, timber, aluminum, or other industry. The program clearly displays the design check formulas used in your design (including a reference to the used equation from the standard). These design check formulas can also be included in the printout report.
When performing a design according to EN 1993‑1‑3, it is possible to graphically display a mode shape for the distortional buckling of a cross-section, and for the RSECTION cross-sections.
The mode shape can also be output in RSECTION 1 for library cross-sections.
Have you activated the Building Model add-on? Very good! This allows you to display the center of rigidity in tabular and graphical form. Use it for your dynamic analysis, for example.
As you've already learned, the results of a Modal Analysis load case are displayed in the program after a successful calculation. You can thus immediately see the first mode shape graphically or as an animation. You can also easily adjust the representation of the mode shape standardization. Do that directly in the Results navigator, where you have one of four options for the visualization of the mode shapes available for the selection:
Scaling the value of the mode shape vector uj to 1 (considers the translation components only)
Selecting the maximum translational component of the eigenvector and setting it to 1
Considering the entire eigenvector (including the rotation components), selecting the maximum, and setting it to 1
Setting the modal mass mi for each mode shape to 1 kg
You can find a detailed explanation of the mode shape standardization in the OnlineManual here.
Compared to the RF‑/STEEL add-on module (RFEM 5 / RSTAB 8), the following new features have been added to the Stress-Strain Analysis add-on for RFEM 6 / RSTAB 9:
Treatment of members, surfaces, solids, welds (line welded joints between two and three surfaces with subsequent stress design)
Output of stresses, stress ratios, stress ranges, and strains
Limit stress depending on the assigned material or a user-defined input
Individual specification of the results to be calculated through freely assignable setting types
Non-modal result details with prepared formula display and additional result display on the cross-section level of members
Is the calculation finished? The results of the modal analysis are then available both graphically and in tables. Display the result tables for the load case or the load cases of the modal analysis. Thus, you can see the eigenvalues, angular frequencies, natural frequencies, and natural periods of the structure at first glance. The effective modal masses, modal mass factors, and participation factors are also clearly displayed.
The new steel sections according to the latest CISC Handbook (12th edition) are available in RFEM 6. The sections are listed in the Standardized library. In the filter, select “Canada” for the region and “CISC 12” for the standard. Alternatively, the section name can be directly entered in the search box located at the bottom of the dialog box.
The design of cold-formed steel members according to the AISI S100-16 / CSA S136-16 is available in RFEM 6. Design can be accessed by selecting “AISC 360” or “CSA S16” as the standard in the Steel Design Add-on. “AISI S100” or “CSA S136” is then automatically selected for the cold-formed design.
RFEM applies the Direct Strength Method (DSM) to calculate the elastic buckling load of the member. The Direct Strength Method offers two types of solutions, numerical (Finite Strip Method) and analytical (Specification). The FSM signature curve and buckling shapes can be viewed under Sections.
After you have completed the design, the program takes care of clearly arranged results. Thus, the program shows you the resulting maximum stresses and stress ratios sorted by section, member/surface, solid, member set, x-location, and so on. In addition to the tabular result values, the add-on shows you the corresponding cross-section graphic with stress points, stress diagram, and values as well. You can relate the design ratio to any kind of stress type. The current location is highlighted in the RFEM/RSTAB model.
In addition to the tabular evaluation, the program offers you even more. You can also graphically check the stresses and design ratios on the RFEM/RSTAB model. It is possible for you to adjust the colors and values individually.
The display of result diagrams of a member or set of members enables you a targeted evaluation. For each design location, you can open the respective dialog box to check the design-relevant section properties and stress components of any stress point. Finally, you have the option of printing the corresponding graphic, including all design details.
Is your goal to determine the number of mode shapes? The program offers you two methods for this. On the one hand, you can manually define the number of the smallest mode shapes to be calculated. In this case, the number of available mode shapes depends on the degrees of freedom (that is, the number of free mass points multiplied by the number of directions in which the masses act). However, it is limited to 9999. On the other hand, you can set the maximum natural frequency the way that the program determined the mode shapes automatically until reaching the natural frequency set.
The governing component temperature at the time of analysis can be determined for the fire resistance design automatically using the input. In this case, you can follow the temperature curve in detail as a function of timeby displaying the temperature-time diagram.
Compared to the RF‑/STEEL EC3 add-on module (RFEM 5 / RSTAB 8), the following new features have been added to the Steel Design add-on for RFEM 6 / RSTAB 9:
In addition to Eurocode 3, other international standards are integrated (such as AISC 360, CSA S16, GB 50017, SP 16.13330)
Consideration of hot-dip galvanizing (DASt guideline 027) in the fire protection design according to EN 1993‑1‑2
Input option for transverse stiffeners that can be taken into account in the shear buckling analysis
Lateral-torsional buckling can also be checked for hollow sections (for example, relevant for slender, high rectangular hollow sections)
Automatic detection of members or member sets valid for the design (for example, automatic deactivation of members with invalid material or members already contained in a member set)
Design settings can be adjusted individually for each member
Graphical display of the results in the gross section or the effective section
Output of the used design check formulas (including a reference to the used equation from the standard)
The Concrete Design add-on allows you to perform the seismic design of reinforced concrete members according to EC 8. This includes, among other things, the following functionalities:
Seismic design configurations
Differentiation of the ductility classes DCL, DCM, DCH
Option to transfer the behavior factor from a dynamic analysis
Check of the limit value for the behavior factor
Capacity design checks of "Strong column - weak beam"
Detailing and particular rules for curvature ductility factor
Detailing and particular rules for local ductility
The Torsional Warping (7 DOF) add-on provides you with numerous new possibilities. For example, you can perform the calculation of member structures in RFEM and RSTAB, taking into account the cross-section warping. You can consider the resulting internal forces (N, Vu, Vv, Mt,pri, Mt,sec, Mu, Mv, Mω) in the equivalent stress analysis of the steel design. Please note: This feature is currently not available for the design standards AISC 360‑16 and GB 50017.
You can select several methods that are available for the eigenvalue analysis:
Direct Methods
The direct methods (Lanczos [RFEM], roots of characteristic polynomial [RFEM], subspace iteration method [RFEM/RSTAB], and shifted inverse iteration [RSTAB]) are suitable for small to medium-sized models. You should only use these fast solver methods if your computer has a larger amount of memory (RAM).
In contrast, this method only requires a small amount of memory. Eigenvalues are determined one after the other. It can be used to calculate large structural systems with few eigenvalues.
Use the Structure Stability add-on to perform a nonlinear stability analysis using the incremental method. This analysis delivers close-to-reality results also for nonlinear structures. The critical load factor is determined by gradually increasing the loads of the underlying load case until the instability is reached. The load increment takes into account nonlinearities such as failing members, supports and foundations, and material nonlinearities. After increasing the load, you can optionally perform a linear stability analysis on the last stable state in order to determine the stability mode.
Did you use the eigenvalue solver of the add-on to determine the critical load factor for the stability analysis? Verz well, you can then display the governing mode shape of the object to be designed as a result. The eigenvalue solver is available for the lateral-torsional buckling analysis, depending on the design standard used. You can also use the internal eigenvalue solver for the general method according to EN 1993‑1‑1, 6.3.4.
Do you want to perform a stability analysis in the Steel Design add-on? Then it is absolutely necessary to define the effective lengths. To do this, define the nodal supports and effective length factors in the input dialog box. For easy documentation and a comprehensible check of the entries, you can also graphically display the nodal supports and the resulting segments with the corresponding effective length factor in the work window of RFEM/RSTAB.
You can find the serviceability limit state design checks in the result tables of the Steel Design add-on. You can display the design results with all the details at each location of the designed members. Furthermore, graphics are available for you with the result diagrams of the design ratios. This gives you a good overview.
You can also integrate all result tables and graphics into the global printout report of RFEM/RSTAB as a part of the steel design results. Thus, you can display and document the deformations of the entire structure as a part of the RFEM/RSTAB functionality independent of the add-on.