Product Features - Search term: Load...

For calculation diagrams, the "2D | Hinge" is available. These hinge diagrams show the hinge response of load situations for nonlinear hinges.

For calculations with several load situations, such as is the case with pushover analyzes and time history analysis, you can evaluate the state of the hinge in each load step.

If you have experimentally determined surface pressures available for a model, you can apply them to a structural model in RFEM 6, process them in RWIND 2, and use them as wind loads in the structural analysis of RFEM 6.

You can find out how to apply the experimentally determined values in this technical article.

The modal relevance factor (MRF) can help you to assess to which extent specific elements participate in a specific mode shape. The calculation is based on the relative elastic deformation energy of each individual member.

The MRF can be used to distinguish between local and global mode shapes. If multiple individual members show significant MRF (for example, > 20%), the instability of the entire structure or a substructure is very likely. On the other hand, if the sum of all MRFs for an eigenmode is around 100%, a local stability phenomenon (for example, buckling of a single bar) can be expected.

Furthermore, the MRF can be used to determine critical loads and equivalent buckling lengths of certain members (for example, for stability design). Mode shapes for which a specific member has small MRF values (for example, < 20%) can be neglected in this context.

The MRF is displayed by mode shape in the result table under Stability Analysis → Results by Members → Effective Lengths and Critical Loads.

The combination wizard provides you with the option to consider more than one initial state. RFEM and RSTAB allow you to specify different initial states (prestress, form-finding, strain, and so on) for the target combinations in the combinatorics.

You can thus, for example, generate load states on the basis of a form-finding analysis with varying imperfections.

Within the "Plastic capacity design | Simplex Method" in RSECTION, the simultaneous variation of shear stresses over the cross-sectional area is performed in addition to the variation of axial stresses. This extended form of analysis allows you to use redistribution reserves, especially for the cross-sections subjected to shear loading, thus loading the cross-sections even more efficiently.

• Analysis of time diagrams and accelerograms (acceleration-time diagrams exciting the supports of a structure)
• Combination of user-defined time diagrams with nodal, member, and surface loads, as well as free and generated loads
• Combination of several independent excitation functions
• Linear implicit Newmark analysis or modal analysis in time history
• Structural damping using Raleigh damping coefficients or Lehr's damping value
• Graphical display of results in calculation diagrams
• Result display in individual time steps or as an envelope during the entire time period
• Extensive library of seismic events (accelerograms)

It is necessary to enter the required force-time diagrams. They can be combined in load cases or load combinations of the type Time History Analysis | Time Diagrams with the loading in order to define where and in which direction the force-time diagrams act.

The second option is to enter acceleration-time diagrams, which can be used in the load cases of the Time History Analysis | Accelerogram type.

All calculation parameters are specified in the time history analysis settings. These include, for example, the type of analysis method and the maximum calculation time.

• Outsource calculation on a computing server in the cloud
• Option to select different powerful computing servers
• Clearly arranged display of all calculation tasks in the Extranet
• Calculated files are available for download for two months
• Virtually unlimited computing capacity using cloud technology

The model and loads are entered as usual in the RFEM interface.

You can start the cloud calculation by selecting an entry in the Calculate menu. Then, select the virtual machine suitable for the task and start the calculation.

After the start, the image is used to create a virtual machine on which the computing server is started. This takes over the calculation of your file.

You can monitor the processing of calculation tasks in the Extranet.

After completing the calculation, you will receive an email with a link to download the calculated file. Large files are compressed into a ZIP archive. Smaller files can be downloaded directly.

As an alternative, there is a link to the calculated file in the Extranet.

The downloaded file is a common RFEM file and can be used for further processing as usual.

With the Concrete Design add-on, you can perform the fatigue design of members and surfaces according to EN 1992‑1‑1, Chapter 6.8.

For the fatigue design, you can optionally select two methods or design levels in the design configurations:

• Design Level 1: Simplified design according to 6.8.6 and 6.8.7(2): The simplified design is performed for frequent action combinations according to EN 1992‑1‑1, Chapter 6.8.6 (2), and EN 1990, Eq. (6.15b) with the traffic loads relevant in the serviceability state. A maximum stress range according to 6.8.6 is designed for the reinforcing steel. The concrete compressive stress is determined by means of the upper and lower allowable stress according to 6.8.7(2).
• Design Level 2: Design of damage equivalent stress acc. to 6.8.5 and 6.8.7(1) (simplified fatigue design): The design using damage equivalent stress ranges is performed for the fatigue combination according to EN 1992‑1‑1, Chapter 6.8.3, Eq. (6.69) with the specifically defined cyclic action Q_fat.

In the Steel Joints add-on, you have this option to consider the preloaded bolts in the calculation of all components.

You can easily activate the prestress using the check box in the bolt parameters, and it has an impact on the stress-strain analysis as well as the stiffness analysis.

The Ponding load type allows you to simulate rain actions on multi-curved surfaces, taking into account the displacements according to the large deformation analysis.

This numerical rainfall process examines the assigned surface geometry and determines which rainfall portions drain away and which rainfall portions accumulate in puddles (water pockets) on the surface. The puddle size then results in a corresponding vertical load for the structural analysis.

For example, you can use this feature in the analysis of approximately horizontal membrane roof geometries subjected to rain loading.

You can display the RWIND results directly in the main program. In the Navigator - Results, select the Wind Simulation Analysis result type from the list above.

Currently, the following results are available, which refer to the RWIND computational mesh:

• Surface pressure
• Surface cp coefficient
• Wall distance y+ (steady flow)

Use the "Import Support Reactions" Load Wizard in RFEM 6 and RSTAB 9 to easily transfer reaction forces from other models. The wizard allows you to connect all or several nodal and line loads of different models with each other in a few steps.

The load transfer from load cases and load combinations can be carried out automatically or manually. It's necessary that the models are saved in the same Dlubal Center project.

The "Import Support Reactions" load wizard supports the concept of positional statics and allows you to digitally connect the individual positions.

Using the "Load Transfer Only" story type, you can consider slabs without stiffness effect in and out of the plane in the Building Model add-on. This element type collects the loads on the slab and transfers them to the supporting elements of a 3D model. Thus, you can simulate secondary components, such as grillage and similar load distribution elements, without any further effect in the 3D model.

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 Joints add-on, you can design connections according to the American standard ANSI/AISC 360‑16. The following design procedures are integrated:

• Load and Resistance Factor Design (LRFD)
• Allowable Stress Design (ASD)

This function provides you with the option to adopt reaction forces from other models as nodal and line loads.

The option not only transfers the reaction load as an action, but digitally couples the support load of the original model with the load size of the target object. The subsequent changes in the original model are automatically adopted in the target model.

This technology supports the concept of positional statics and allows you to digitally connect the individual positions of the same Dlubal Center project.

Would you like to display nodal loads or load components that act on one point next to each other? Then use the "Shifted Display" option. This allows you to define offsets in the x, y, and z directions, as well as the size and spacing.

Use RWIND 2 Pro to easily apply a permeability to a surface. All you need is the definition of

• the Darcy coefficient D,
• the inertial coefficient I, and
• the length of the porous medium in the direction of flow L,

to define a pressure boundary condition between the front and back of a porous zone. Due to this setting, you obtain the flow through this zone with a two-part result display on both sides of the zone area.

But that's not all. Furthermore, the generation of a simplified model recognizes permeable zones and takes into account the corresponding openings in the model coating. Can you waive an elaborate geometric modeling of the porous element? Understandable – we have good news for you then! With a pure definition of the permeability parameters, you can avoid complex geometric modeling of the porous element. Use this feature to simulate permeable scaffolding, dust curtains, mesh structures, and so on.

Do you already know the editor for mesh refinement control? It is a great help for your work! Why? It's easy – it gives you the following options:

• Graphic visualization of the areas with mesh refinements
• Mesh refinement of zones
• Deactivating the standard 3D solid mesh refinement with transversion into the corresponding manual 3D mesh refinements.

These options help you to formulate a suitable rule for meshing the entire model, even for the models with unusual dimensions. Use the editor to efficiently define small model details on large buildings or detailed meshing areas in the coating area of the model. You will be amazed!

Steel bolted connections with gusset plates on the canopy structure.

Download the structural analysis model and open it with the finite element program RFEM 6 using Steel Joints Add-on.

Did you already know? For load combinations, you can optionally display the difference results to the initial state. For example, you have the option for a geotechnical analysis to output the settlement as a difference to the initial state "soil self-weight".

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.

Are you ready for the evaluation? Use the calculation diagrams, which show the distribution of a specific result during the calculation.

You can freely define the layout of the vertical and horizontal axes of the calculation diagram. This allows you, for example, to consider the settlement distribution of a certain node, depending on the load.