In the Steel Joints add-on, you can connect circular hollow sections using welds.
It is possible to connect the circular sections to each other or to planar structural components. The fillets of standard and thin-walled sections can also be connected with a weld.
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
In the Steel Design add-on, you can perform the stability and cross-section design checks of cold-formed sections according to EN 1993‑1‑3 in compliance with Sections 6.1.2 – 6.1.5 and 6.1.8 – 6.1.10.
In the Steel Joints add-on, you can classify the joint stiffnesses.
In addition to the initial stiffness, the table also shows the limit values for hinged and rigid connections for the selected internal forces N, My, and/or Mz. The resulting classification is then displayed in tables as "hinged", "semi-rigid", or "rigid".
In the "Steel Joints" add-on, you can consider preloaded bolts in all components during the calculation. You can easily activate the preloading using the check box in the bolt parameters, and it has an impact on the stress-strain analysis as well as the stiffness analysis.
Preloaded bolts are special bolts used in steel structures to generate a high clamping force between the connected structural components. This clamping force causes friction between the structural components, which allows for the transfer of forces.
Functionality Preloaded bolts are tightened with a certain torque, causing them to stretch and generate a tensile force. This tensile force is transferred to the connected components and leads to a high clamping force. The clamping force prevents the connection from loosening and ensures safe force transmission.
Advantages
High load-bearing capacity: Preloaded bolts can transfer large forces.
Low deformation: They minimize the deformation of the connection.
Fatigue strength: They are resistant to fatigue.
Easy assembly: They are relatively easy to assemble and disassemble.
Analysis and Design The calculation of preloaded bolts is performed in RFEM using the FE analysis model generated by the "Steel Joints" add-on. It takes into account the clamping force, friction between structural components, shear strength of bolts, and load-bearing capacity of the structural components. The design is carried out according to DIN EN 1993‑1‑8 (Eurocode 3) or the US standard ANSI/AISC 360‑16. You can save the created analysis model, including the results, and use it as an independent RFEM model.
The initial stiffness Sj,ini is a crucial parameter for evaluating whether a connection can be characterized as rigid, semi-rigid, or pinned.
In the "Steel Joints" add-on, you can calculate the initial stiffness Sj,ini according to Eurocode (EN 1993‑1‑8, Section 5.2.2) and AISC (AISC 360-16, Cl. E3.4) with regard to the internal forces N, My, and/or Mz.
The optional automatic transfer of initial stiffnesses allows for a directly transfer as member hinge stiffnesses in RFEM. The entire structure is then recalculated and the resulting internal forces are automatically adopted as loads in the analysis and design of the connection models.
This automated iteration process eliminates the need for manual export and import of data, reducing the amount of work and minimizing potential sources of error.
The pushover analysis is managed by a newly introduced analysis type in the load combinations. Here, you have access to the selection of the horizontal load distribution and direction, the selection of a constant load, the selection of the desired response spectrum for the determination of the target displacement, and the pushover analysis settings tailored to the pushover analysis.
In the pushover analysis settings, you can modify the increment of the increasing horizontal load and specify the stopping condition for the analysis. Furthermore, it is possible to easily adjust the precision for the iterative determination of the target displacement.
Consideration of nonlinear component behavior using plastic standard hinges for steel (FEMA 356, EN 1998‑3) and nonlinear material behavior (masonry, steel - bilinear, user-defined working curves)
Direct import of masses from load cases or combinations for the application of constant vertical loads
User-defined specifications for the consideration of horizontal loads (standardized to a mode shape or uniformly distributed over the height of the masses)
Determination of a pushover curve with selectable limit criterion of the calculation (a collapse or limit deformation)
Transformation of the pushover curve into the capacity spectrum (ADRS format, single degree of freedom system)
Bilinearization of the capacity spectrum according to EN 1998‑1:2010 + A1:2013
Transformation of the applied response spectrum into the required spectrum (ADRS format)
Determination of target displacement according to EC 8 (the N2 method according to Fajfar 2000)
Graphical comparison of the capacity and required spectrum
Graphical evaluation of the acceptance criteria of predefined plastic hinges
Result display of the values used in the iterative calculation of the target displacement
Access to all results of the structural analysis in the individual load levels
During the calculation, the selected horizontal load is increased in load steps. A static nonlinear analysis is carried out for each load step until reaching the specified limit condition.
The results of the pushover analysis are extensive. On one hand, the structure is analyzed for its deformation behavior. This can be represented by a force-deformation line of the system (a capacity curve). On the other hand, the response spectrum effect can be displayed in the ADRS display (Acceleration-Displacement Response Spectrum). The target displacement is automatically determined in the program based on these two results. The process can be evaluated graphically and in tables.
The individual acceptance criteria can then be graphically evaluated and assessed (for the next load step of the target displacement, but also for all other load steps). The results of the static analysis are also available for the individual load steps.
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.
In the Steel Joint add-on, you can design the connections of members with composite cross-sections. Furthermore, you can perform joint design checks for almost all thin-walled cross-sections in the RFEM library.
Here, the weld design becomes child's play. Using the specially developed material model "Orthotropic | Plastic | Weld (Surfaces)", you can calculate all stress components plastically. The stress τperpendicular is also considered plastically.
Using this material model you can design welds closer to reality and more efficiently.
Using the "Connecting Plate" component, you can automatically create a new gusset plate in the Steel Joints add-on. This saves you separate components, and the other elements, such as a cap plate and a slide plate, are thus automatically taken into account with their dimensions.
If a weld seam connects two plates with different materials, it is possible to select from a combo box in the Steel Joints add-on which one of both materials should be used for the weld seam.
Would you like to perform cross-section design checks for cold-formed steel members according to EN 1993‑1‑3? No matter if you design the cold-formed sections from the cross-section library or the general cold-formed (non-perforated) sections from RSECTION – your structural analysis program helps you to determine the effective cross-section, taking into account the local buckling and instability. You can also perform a cross-section check according to EN 1993‑1‑3, 6.1.6. In this case, the internal forces from the calculation using Torsional Warping (7 DOF) are taken into account by means of the equivalent stress check
In the case of rectangular cross-sections, you can usually achieve a direct connection by using welds. However, you can also connect them to other cross-sections in the same way. Furthermore, other components such as end plates help you to connect the rectangular cross-sections to other structural components.
The Aluminum Design add-on provides you with further options. Here you can also design general cross-sections that are not predefined in the cross-section library. For example, create a cross-section in the RSECTION program and then import it into RFEM/RSTAB. Depending on the design standard used, you can select from various design formats. This includes, for example, the equivalent stress analysis.
With a license for RSECTION and "Effective Sections", you can also perform the design checks while taking into account the effective cross-section properties according to EN 1993‑1‑5.
You know for sure that when connecting tension-loaded components with bolted connections, you need to consider the cross-section reduction due to the bolt holes in the ultimate limit state design. The structural analysis programs also have a solution for this. In the Aluminum Design add-on, you can enter a member local section reduction for this. Enter the reduction of the cross-section as an absolute value or as a percentage of the total area at all relevant locations.
Did you use the eigenvalue solver of the add-on to determine the critical load factor within the stability analysis? In this case, you can then display the governing mode shape of the object to be designed as a result.
The program does a lot of work for you. For example, the load or result combinations required for the serviceability limit state are generated and calculated in RFEM/RSTAB. You can select these design situations for the deflection analysis in the Aluminum Design add-on. Depending on the specified precamber and reference system, the program determines the deformation values at each location of a member. They are then compared to the limit values.
You can specify the deformation limit value individually for each structural component in Serviceability Configuration. In this case, you define the maximum deformation depending on the reference length as the allowable limit value. By defining design supports, you can segment the components. In this way, you can determine the corresponding reference length automatically for each design direction.
And that's not all. Based on the position of the assigned design supports, the program allows you to automatically determine the distinction between beams and cantilevers. The limit value is thus determined accordingly.
You can find the serviceability limit state design checks in the result tables of the Aluminum Design add-on. They are already fully integrated there. You have the option to display the design results with all the details at each location of the designed members. You can also use graphics with the result diagrams of the design ratios.
You can integrate all result tables and graphics into the global printout report of RFEM/RSTAB as a part of the aluminum design results. RFEM/RSTAB also allows you to display and document the deformations of the entire structure independently of the add-on.
Do you prefer it clear? So do we! That's why all performed design checks for the design standard are displayed for you in a clear way. You determine a design criterion for each design check. You get design details, which include the initial values, intermediate results, and final results, arranged in a structured way for each design check. You can find the calculation process with the applied formulas, standard sources, and results in great detail in an information window in the design details.
You can find the design checks displayed in tables in the Aluminum Design add-on. Moreover, you can display the distribution of the design ratios graphically. Extensive filter options are available for you both in the table as well as in the graphical output. You can thus specifically display the desired design checks by limit state or design type in the program.
When calculating the deflection limit, you have to consider certain reference lengths. You can define these reference lengths and the segments to be checked independently of each other, depending on the direction. For this, define design supports at the intermediate nodes of a member and assign them to the respective direction for the deformation analysis. Thus, the segments are created where you can define a precamber for each direction and segment.
Note that the definition of the effective lengths in the Aluminum Design add-on is an essential requirement for the stability analysis. For this, define the nodal supports and effective length factors in the input dialog box. Do you want to clearly document the nodal supports and the resulting segments with the associated effective length factors? To check the input data, it is best for you to use the graphic display in the RFEM/RSTAB work window. Thus, you can comprehend the design at any time with minimum effort.
As usual, you enter the structural system and calculate the internal forces in the programs RFEM and RSTAB. You have unlimited access to the extensive material and cross-section libraries. Did you know that you can create general cross-sections using the RSECTION program? That saves you a lot of work.
Don't be afraid of additional windows and input chaos! Aluminum Design is completely integrated into the main programs and automatically takes into account the structure and the available calculation results. You can directly assign further entries for the aluminum design, such as effective lengths, cross-section reductions, or design parameters, to the objects to be designed. You can simply and efficiently select the elements graphically using the [Select] function.