In the Steel Joint add-on, you can use not only the usual member types of "Beam", "Truss", and so on, but also the member type of "Result Beam", as well as cross-sections from surface elements. You should select a suitable cross-section for the result beam and then define any member openings in the surface model using the member editor.
The "Surface Contact" component in the Steel Joints add-on allows you to take into account a pressure contact between two parallel plates/member plates. Furthermore, you can optionally consider the friction between the surfaces.
The "Results by Story" table of a building model shows the center of gravity for load cases and load combinations. In addition to the self-weight, the vertical loads of the respective load cases and load combinations are also taken into account.
You can also use the "Center of Gravity and Information About Selected Objects" dialog box to display the center of gravity, taking into account the selected loading.
In the Dlubal Center, there is an extensive library with connections available for the Steel Joints add-on.
You can access this library directly from the add-on and assign the predefined connections to the corresponding nodes. You can also save user-defined connections in the library in Dlubal Center.
In the Steel Joint add-on, you can arrange plates in various geometry shapes. In addition to the "Rectangle" and "Circle" shapes, the "Polygon" shape is also available. The polygonal shape is defined by entering the point coordinates.
When modeling stories, you can use the "Semi-Rigid Diaphragm" option for slabs.
In principle, this modeling option selects the same approach as for the "Rigid Diaphragm" modeling of stories. In contrast to the rigid diaphragm, no nodal coupling is carried out from the center of gravity to each FE node. This way, it is possible to take into account the flexibility of the slab.
The "Stub" component is available to you in the Steel Joints add-on. It allows you to extend a member using a purlin joint with another member (stub) and to connect it to a reference component.
In the Steel Joint add-on, you can define several ribs at the same time on one member or plate. The distribution can be carried out according to an orthogonal and a polar pattern.
The "Base Plate" component allows you to design base plate connections with cast-in anchors. In this case, plates, welds, anchorages, and steel-concrete interaction are analyzed.
You can neglect openings with a certain area in the building model calculation. This function can be activated in the global settings of the building stories. A warning message appears saying that the openings have been neglected.
Using the "Rib" component, you can define any number of longitudinal ribs on a member plate. By defining a reference object, you can automatically specify welds on it.
The "Rib" component can also be arranged on circular hollow sections. This requires an additional definition of the angle between the ribs.
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.
Shear walls and deep beams of a building model are available as independent objects in the design add-ons. This allows for faster filtering of the objects in results, as well as better documentation in the printout report.
You can now insert a cap plate in Steel Joints with just a few clicks. You can enter the data using the known definition types "Offsets" or "Dimensions and Position". By specifying a reference member and the cutting plane, it is also possible to omit the Member Cut component.
This component allows you to easily model cap plates on column ends, for example.
The building story generator in the Building Model add-on provides you with the option to automatically create building stories, depending on the topology of the model.
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 MRFs (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.
You can use the "Plate Cut" component to cut plates (for example, gusset plates, fin plates, and so on). Various cutting methods are available:
Plane: The cut is performed on the closest surface to the reference plate.
Surface: Only the intersecting parts of plates are cut.
Bounding Box: The outermost dimension consisting of width and height is cut out of the plate as a rectangle.
Convex Hull: The outer hull of the cross-section is used for the plate cut. If there are fillets at the corner nodes of the cross-section, the cut is adapted to them.
Plates and structural elements can be precisely cut using the "Auxiliary Solid" component in the Steel Joint add-on. Within this component, you can use the shapes of a box, a cylinder, or any cross-section as a guide object.
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.
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 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.