Did you know that you can also display the moment-axial force interaction diagrams (M‑N diagrams) graphically? This allows you to display the cross-section resistance in the case of an interaction of a bending moment and an axial force. In addition to the interaction diagrams related to the cross-section axes (My‑N diagram and Mz‑N diagram), you can also generate an individual moment vector to create an Mres‑N interaction diagram. You can display the section plane of the M‑N diagrams in the 3D interaction diagram. The program displays the corresponding value pairs of the ultimate limit state in a table. The table is dynamically linked to the diagram so that the selected limit point is also displayed in the diagram.
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.
Reinforced concrete usually answers the question "How much can you carry?" simply with "Yes". Nevertheless, you need a three-dimensional moment-moment-axial force interaction diagram for the graphical output of the ultimate limit state of reinforced concrete cross-sections. The Dlubal structural analysis software offers you just that.
With the additional display of the load action, you can easily recognize or visualize whether the limit resistance of a reinforced concrete cross-section is exceeded. Since you can control the diagram properties, you can customize the appearance of the My-Mz-N diagram to suit your needs.
Do you work with the structural components consisting of slabs? In that case, you have to perform the shear force design with the requirements of punching shear design, for example, according to 6.4, EN 1992‑1‑1. In addition to floor slabs, you can also design foundation slabs in this way.
In the Ultimate Configuration for concrete design, you can define the punching design parameters for the selected nodes.
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.
Time-dependent concrete properties, such as creep and shrinkage, are very important for your calculation. You can define them directly for the material in the structural analysis program. In the input dialog box, the time course of the creep or shrinkage function is displayed to you graphically. You can easily select the modification of the applied concrete age, for example, due to a temperature treatment.
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.
Depending on the axial force N, you can generate a moment curvature line for any moment vector. The program also shows you the value pairs of the displayed diagram in a table. Furthermore, you can activate the secant stiffness and tangent stiffness of the reinforced concrete cross-section, belonging to the moment curvature diagram, as an additional diagram.
You can display the existing stresses and strains of a concrete cross-section and the reinforcement as a 3D stress image or 2D graphic. Depending on which results do you select in the result tree of the design details, the stresses or strains are displayed to you in the defined longitudinal reinforcement under the load actions or the limit internal forces.
In the Concrete Design add-on, you can design any RSECTION cross-section. Define the concrete cover, shear force, and longitudinal reinforcement directly in RSECTION.
After importing the reinforced RSECTION cross-section into RFEM 6 or RSTAB 9, you can use it for design in the Concrete Design add-on.
You have the option to automatically design the existing surface reinforcement to cover the required reinforcement. You can also select whether to automatically define the reinforcement diameter or the member spacing.
You can perform the calculation of the warping torsion on the entire system. Thus, you consider the additional 7th degree of freedom in the member calculation. The stiffnesses of the connected structural elements are automatically taken into account. It means, you don't need to define equivalent spring stiffnesses or support conditions for a detached system.
You can then use the internal forces from the calculation with warping torsion in the add-ons for the design. Consider the warping bimoment and the secondary torsional moment, depending on the material and the selected standard. A typical application is the stability analysis according to the second-order theory with imperfections in steel structures.
Did you know that The application is not limited to thin-walled steel cross-sections. Thus, it is possible for you, for example, to perform the calculation of the ideal overturning moment of beams with solid timber cross-sections.
Compared to the RF-/STEEL Warping Torsion add-on module (RFEM 5 / RSTAB 8), the following new features have been added to the Torsional Warping (7 DOF) add-on for RFEM 6 / RSTAB 9:
Complete integration into the environment of RFEM 6 and RSTAB 9
7th degree of freedom is directly taken into account in the calculation of members in RFEM/RSTAB on the entire system
No more need to define support conditions or spring stiffnesses for calculation on the simplified equivalent system
Combination with other add-ons is possible, for example for the calculation of critical loads for torsional buckling and lateral-torsional buckling with stability analysis
No restriction to thin-walled steel sections (it is also possible to calculate ideal overturning moments for beams with massive timber sections, for example)
You can specify the shear and longitudinal reinforcement individually for each member. In this case, there are various templates available for entering the reinforcement.
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.
You determine the deformation for members and surfaces, taking into account the cracked (state II) or non-cracked (state I) reinforced concrete cross-section. When determining the stiffness, you can consider "tension stiffening" between the cracks according to the design standard used.
Do you want to determine the biaxial bending resistance of a reinforced concrete cross-section? For this, you have to activate a moment-moment interaction diagram (My-Mz diagram) first. This My-Mz diagram represents a horizontal section through the three-dimensional diagram for the specified axial force N. Due to the coupling to the 3D interaction diagram, you can also visualize the section plane there.
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.
Consideration of 7 local deformation directions (ux, uy, uz, φx, φy, φz, ω) or 8 internal forces (N, Vu, Vv, Mt,pri, Mt,sec, Mu, Mv, Mω) when calculating member elements
Usable in combination with a structural analysis according to linear static, second-order, and large deformation analysis (imperfections can also be taken into account)
In combination with the Stability Analysis add-on, allows you to determine critical load factors and mode shapes of stability problems such as torsional buckling and lateral-torsional buckling
Consideration of end plates and transverse stiffeners as warping springs when calculating I-sections with automatic determination and graphical display of the warping spring stiffness
Graphical display of the cross-section warping of members in the deformation
In the "Shear Reinforcement" tab, you can select the option "Cross-ties over free rebars with active selection in graphic". It allows you to arrange additional cross-ties on free rebars of the longitudinal reinforcement.
You can activate or deactivate the position of the cross-ties in the Info Graphic. The cross-ties are applied for the ultimate limit state design and the structural design checks. They are available for the design according to EN 1992‑1‑1.
Within a member, you can define the integration width and effective slab width of T-beams (ribs) with different widths. The member is divided into segments. You can either grade or specify the transition between the different flange widths as linearly variable. Furthermore, the program allows you to consider the defined surface reinforcement as a flange reinforcement for the reinforced concrete design of a rib.
The Concrete Design add-on allows you to design fiber-reinforced concrete components according to the guideline "DAfStb Steel Fiber-Reinforced Concrete".
You can use this option for the design according to EN 1992‑1‑1. The design according to the DAfStb guideline is carried out once the concrete of the "Fiber Concrete" type has been assigned to the reinforced structural component.
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
Enter the surface reinforcement directly on the RFEM level. In this case, you can select the defined area reinforcements individually. The usual editing functions Copy, Mirror, or Rotate are at your disposal when entering the surface reinforcement.
The structural analysis program provides you with a clear overview of all performed design checks for the design standard. You have to determine a design criterion for each design check. In addition to the ultimate limit state and the serviceability limit state design, the program checks the design rules of the standard. For each design check, there are the design details including the initial values, intermediate results, and final results, arranged in a structured way. An information window in the design details shows you the calculation process with the applied formulas, standard sources, and results in great detail.
During the cross-section design, you can directly control whether the concrete surface is applied behind the reinforcing bars or is subtracted from the concrete cross-section. You can use the design of the net concrete cross-section especially in the case you deal with a highly reinforced cross-section.