For many parts in engineering, the finite element method is used to provide a safe design. Structural engineers typically work with 1D members and surfaces. In some cases, however, it is required to take also the thickness of the material into account. The FEA package RFEM allows intuitive modeling of steel parts such as joints or connection parts that require high strength.
Following the increasing demand in that field, the Dlubal partners RFEM NL and RFEM BE organized an info day with focus on modeling and designing steel details using solids in RFEM.
Engineers Value the Great Variety of Design Options in RFEM
In three different presentations, Emiel Peltenburg from RFEM NL and Walter Rustler from Dlubal Software Germany highlighted the powerful modeling and analysis options in RFEM. Emiel Peltenburg modeled a grout anchor in RFEM. In this session, principle modeling techniques in RFEM were explained.
In the second part, Walter Rustler gave an insight into the theoretical background of the solid elements in RFEM. Solids are especially helpful for simulating contact problems and for thick parts where stresses in three directions need to be investigated. Also, in many exchange formats that are used in mechanical engineering applications, the models are represented in a 3D volumetric geometry.
In several practical examples, Walter Rustler demonstrated the flexibility of RFEM: steel or timber frame analysis, a concrete slab or glass design are possible within one program. Users do not have to buy different products with additional maintenance and support contracts or do not have extra costs for training for different products. Hence, Dlubal Software offers very versatile tools to handle a wide range of engineering problems.
Solids and Parametric Bolt Modeling
Solids can be extruded from simple surfaces in RFEM to regular basic types like cubes or rings. For curved or more complex shapes, it is possible to compose solids with a selection of boundary surfaces. RFEM automatically recognizes if an enclosed space is defined and creates a solid. In steel connections it is vital to be able to handle contact of two surfaces. In RFEM, it is thus possible to define compression-only conditions including friction effects as it typically appears at end plate connections. A very effective way to model bolts is to combine beam elements with compression-only surfaces. The surfaces connect the bolt and the surrounding material of a solid only if compression is present. These models can also be parametric and inserted as a block. The user has to adjust only the parameters and then assemble the connection. This method was also presented by Walter Rustler when modeling a tie rod connector.
Once a model is defined in a CAD application, it is possible to export it to a STEP or IGES file. These formats describe the 3D geometry of the model. It is usually not easy to create simplified 1D beam models or shell models from volumetric parts in a program. Sometimes it is easier to just take the 3D geometry as it is and to deal with the more complex analysis. In such a case, RFEM can import those files, visualize the geometry and semi-automatically assist the user to create solids. RFEM is then able to perform also a plastic analysis of such structures.
Info Day Recordings Available on YouTube
If you could not attend the event, you can view the recording of the presentation online: